Charging policy information for a packet data unit session of a wireless device

ABSTRACT

A charging function (CHF) receives, from a policy control function (PCF), a first request for charging policy information for a packet data unit (PDU) session of a wireless device. The charging policy information is determined for the PDU session of the wireless device. The charging policy information indicates a charging method comprising one or more of: online charging; offline charging; and converged charging. A message comprising the charging policy information is sent to the PCF. The CHF receives from a session management function (SMF), a second request to establish a charging session. The second request comprises the charging method. A confirmation for the charging method is sent to the SMF.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent Ser. No. 16/564,236,filed Sep. 9, 2019, which claims the benefit of U.S. ProvisionalApplication No. 62/730,850, filed Sep. 13, 2018, which are herebyincorporated by reference in their entirety.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

Examples of several of the various embodiments of the present inventionare described herein with reference to the drawings.

FIG. 1 is a diagram of an example 5G system architecture as per anaspect of an embodiment of the present disclosure.

FIG. 2 is a diagram of an example 5G System architecture as per anaspect of an embodiment of the present disclosure.

FIG. 3 is a system diagram of an example wireless device and a networknode in a 5G system as per an aspect of an embodiment of the presentdisclosure.

FIG. 4 is a system diagram of an example wireless device as per anaspect of an embodiment of the present disclosure.

FIG. 5A and FIG. 5B depict two registration management state models inUE 100 and AMF 155 as per an aspect of embodiments of the presentdisclosure.

FIG. 6A and FIG. 6B depict two connection management state models in UE100 and AMF 155 as per an aspect of embodiments of the presentdisclosure.

FIG. 7 is diagram for classification and marking traffic as per anaspect of an embodiment of the present disclosure.

FIG. 8 and FIG. 9 is an example call flow for registration procedure asper an aspect of an embodiment of the present disclosure.

FIG. 10 is a diagram of an example 5G policy and charging control systemarchitecture as per an aspect of an embodiment of the presentdisclosure.

FIG. 11 is an example call flow for PDU session establishment chargingas per an aspect of an embodiment of the present disclosure.

FIG. 12 is an example call flow of PCF makes policy decision based oncharging policy information received from a CHF as per an aspect of anembodiment of the present disclosure.

FIG. 13 is a diagram depicting an example definition of informationelement for charging policy information as per an aspect of anembodiment of the present disclosure.

FIG. 14 is an example diagram depicting the procedures of PCF as per anaspect of an embodiment of the present disclosure.

FIG. 15 is an example diagram depicting the procedures of CHF as per anaspect of an embodiment of the present disclosure.

FIG. 16 is an example diagram depicting the procedures of SMF as per anaspect of an embodiment of the present disclosure.

FIG. 17 is an example call flow of PCF makes policy decision based oncharging policy information received from a NF as per an aspect of anembodiment of the present disclosure.

FIG. 18 is an example call flow of CHF updates charging policyinformation as per an aspect of an embodiment of the present disclosure.

FIG. 19 is an example call flow of selecting a CHF by an NRF as per anaspect of an embodiment of the present disclosure.

FIG. 20 is a flow diagram as per an aspect of an example embodiment ofthe present disclosure.

FIG. 21 is a flow diagram as per an aspect of an example embodiment ofthe present disclosure.

DETAILED DESCRIPTION OF EXAMPLES

Example embodiments of the present invention enable implementation ofenhanced features and functionalities in 5G systems. More particularly,the embodiments of the technology disclosed herein may relate to policyand charging control (e.g. for 5G or future communication system).Throughout the present disclosure, UE, wireless device, and mobiledevice are used interchangeably.

The following acronyms are used throughout the present disclosure:

5G 5th generation mobile networks

5GC 5G Core Network

5GS 5G System

5G-AN 5G Access Network

5QI 5G QoS Indicator

AF Application Function

AMBR Aggregate Maximum Bit Rate

AMF Access and Mobility Management Function

AN Access Network

APN Access Point Name

ARP Allocation and Retention Priority

BD Billing Domain

CDR Charging Data Record

CHF Charging Function

CN Core Network

CP Control Plane

DDoS Distributed Denial of Service

DL Downlink

DN Data Network

DN-AAA Data Network Authentication Authorization and Accounting

DNN Data Network Name

EPS Evolved Packet System

FDD Frequency Division Duplex

FQDN Fully Qualified Domain Name

GPSI Generic Public Subscription Identifier

GW Gateway

HTTP Hypertext Transfer Protocol

ID Identifier

IMS IP Multimedia core network Subsystem

IP Internet Protocol

IP-CAN IP Connectivity Access Network

L2 Layer 2 (data link layer)

L3 Layer 3 (network layer)

LADN Local Area Data Network

LAN local area network

MAC Media Access Control

MICO Mobile Initiated Connection Only

N3IWF Non-3GPP InterWorking Function

NAS Non Access Stratum

NAT Network address translation

NEF Network Exposure Function

NF Network Function

NR New Radio

NG-RAN NR Radio Access Network

NRF Network Repository Function

NSI Network Slice Instance

NSSAI Network Slice Selection Assistance Information

NSSF Network Slice Selection Function

NWDAF Network Data Analytics Function

OAM Operation Administration and Maintenance

PCC Policy and Charging Control

PCF Policy Control Function

PDU Packet Data Unit

PEI Permanent Equipment Identifier

PLMN Public Land Mobile Network

QFI QoS Flow Identifier

QoS Quality of Service

RA Random Access

RAN Radio Access Network

RAT Radio Access Technology

RRC Radio Resource Control

RM Registration Management

SBA Service Based Architecture

SM Session Management

SMF Session Management Function

SMSF SMS Function

S-NSSAI Single Network Slice Selection Assistance information

SS Synchronization Signal

SSC Session and Service Continuity

SUPI Subscriber Permanent Identifier

TA Tracking Area

TAI Tracking Area Identity

TCP Transmission Control Protocol

UDR Unified Data Repository

UDM Unified Data Management

UDP User Datagram Protocol

UE User Equipment

UL Uplink

UL CL Uplink Classifier

UPF User Plane Function

XML Extensible Markup Language

Example FIG. 1 and FIG. 2 depict a 5G system comprising of accessnetworks and 5G core network. An example 5G access network may comprisean access network connecting to a 5G core network. An access network maycomprise an NG-RAN 105 and/or non-3GPP AN 165. An example 5G corenetwork may connect to one or more 5G access networks 5G-AN and/orNG-RANs. 5G core network may comprise functional elements or networkfunctions as in example FIG. 1 and example FIG. 2 where interfaces maybe employed for communication among the functional elements and/ornetwork elements.

In an example, a network function may be a processing function in anetwork, which may have a functional behavior and/or interfaces. Anetwork function may be implemented either as a network element on adedicated hardware, and/or a network node as depicted in FIG. 3 and FIG.4 , or as a software instance running on a dedicated hardware and/orshared hardware, or as a virtualized function instantiated on anappropriate platform.

In an example, access and mobility management function, AMF 155, mayinclude the following functionalities (some of the AMF 155functionalities may be supported in a single instance of an AMF 155):termination of RAN 105 CP interface (N2), termination of NAS (N1), NASciphering and integrity protection, registration management, connectionmanagement, reachability management, mobility management, lawfulintercept (for AMF 155 events and interface to LI system), providetransport for session management, SM messages between UE 100 and SMF160, transparent proxy for routing SM messages, access authentication,access authorization, provide transport for SMS messages between UE 100and SMSF, security anchor function, SEA, interaction with the AUSF 150and the UE 100, receiving the intermediate key established as a resultof the UE 100 authentication process, security context management, SCM,that receives a key from the SEA that it uses to derive access networkspecific keys, and/or the like.

In an example, the AMF 155 may support non-3GPP access networks throughN2 interface with N3IWF 170, NAS signaling with a UE 100 over N3IWF 170,authentication of UEs connected over N3IWF 170, management of mobility,authentication, and separate security context state(s) of a UE 100connected via non-3GPP access 165 or connected via 3GPP access 105 andnon-3GPP access 165 simultaneously, support of a coordinated RM contextvalid over 3GPP access 105 and non 3GPP access 165, support of CMmanagement contexts for the UE 100 for connectivity over non-3GPPaccess, and/or the like.

In an example, an AMF 155 region may comprise one or multiple AMF 155sets. The AMF 155 set may comprise some AMF 155 that serve a given areaand/or network slice(s). In an example, multiple AMF 155 sets may be perAMF 155 region and/or network slice(s). Application identifier may be anidentifier that may be mapped to a specific application trafficdetection rule. Configured NSSAI may be an NSSAI that may be provisionedin a UE 100. DN 115 access identifier (DNAI), for a DNN, may be anidentifier of a user plane access to a DN 115. Initial registration maybe related to a UE 100 registration in RM-DEREGISTERED 500, 520 states.N2AP UE 100 association may be a logical per UE 100 association betweena 5G AN node and an AMF 155. N2AP UE-TNLA-binding may be a bindingbetween a N2AP UE 100 association and a specific transport networklayer, TNL association for a given UE 100.

In an example, session management function, SMF 160, may include one ormore of the following functionalities (one or more of the SMF 160functionalities may be supported in a single instance of an SMF 160):session management (e.g. session establishment, modify and release,including tunnel maintain between UPF 110 and AN 105 node), UE 100 IPaddress allocation & management (including optional authorization),selection and control of UP function(s), configuration of trafficsteering at UPF 110 to route traffic to proper destination, terminationof interfaces towards policy control functions, control part of policyenforcement and QoS, lawful intercept (for SM events and interface to LISystem), termination of SM parts of NAS messages, downlink datanotification, initiation of AN specific SM information, sent via AMF 155over N2 to (R)AN 105, determination of SSC mode of a session, roamingfunctionality, handling local enforcement to apply QoS SLAs (VPLMN),charging data collection and charging interface (VPLMN), lawfulintercept (in VPLMN for SM events and interface to LI System), supportfor interaction with external DN 115 for transport of signaling for PDUsession authorization/authentication by external DN 115, and/or thelike.

In an example, a user plane function, UPF 110, may include one or moreof the following functionalities (some of the UPF 110 functionalitiesmay be supported in a single instance of a UPF 110): anchor point forIntra-/Inter-RAT mobility (when applicable), external PDU session pointof interconnect to DN 115, packet routing & forwarding, packetinspection and user plane part of policy rule enforcement, lawfulintercept (UP collection), traffic usage reporting, uplink classifier tosupport routing traffic flows to a data network, branching point tosupport multi-homed PDU session(s), QoS handling for user plane, uplinktraffic verification (SDF to QoS flow mapping), transport level packetmarking in the uplink and downlink, downlink packet buffering, downlinkdata notification triggering, and/or the like.

In an example, the UE 100 IP address management may include allocationand release of the UE 100 IP address and/or renewal of the allocated IPaddress. The UE 100 may set a requested PDU type during a PDU sessionestablishment procedure based on its IP stack capabilities and/orconfiguration. In an example, the SMF 160 may select PDU type of a PDUsession. In an example, if the SMF 160 receives a request with PDU typeset to IP, the SMF 160 may select PDU type IPv4 or IPv6 based on DNNconfiguration and/or operator policies. In an example, the SMF 160 mayprovide a cause value to the UE 100 to indicate whether the other IPversion is supported on the DNN. In an example, if the SMF 160 receivesa request for PDU type IPv4 or IPv6 and the requested IP version issupported by the DNN the SMF 160 may select the requested PDU type.

In an example embodiment, the 5GC elements and UE 100 may support thefollowing mechanisms: during a PDU session establishment procedure, theSMF 160 may send the IP address to the UE 100 via SM NAS signaling. TheIPv4 address allocation and/or IPv4 parameter configuration via DHCPv4may be employed once PDU session may be established. IPv6 prefixallocation may be supported via IPv6 stateless autoconfiguration, ifIPv6 is supported. In an example, 5GC network elements may support IPv6parameter configuration via stateless DHCPv6.

The 5GC may support the allocation of a static IPv4 address and/or astatic IPv6 prefix based on subscription information in a UDM 140 and/orbased on the configuration on a per-subscriber, per-DNN basis.

User plane function(s) (UPF 110) may handle the user plane path of PDUsessions. A UPF 110 that provides the interface to a data network maysupport functionality of a PDU session anchor.

In an example, a policy control function, PCF 135, may support unifiedpolicy framework to govern network behavior, provide policy rules tocontrol plane function(s) to enforce policy rules, implement a front endto access subscription information relevant for policy decisions in auser data repository (UDR), and/or the like.

A network exposure function, NEF 125, may provide means to securelyexpose the services and capabilities provided by the 3GPP networkfunctions, translate between information exchanged with the AF 145 andinformation exchanged with the internal network functions, receiveinformation from other network functions, and/or the like.

In an example, a network repository function, NRF 130 may supportservice discovery function that may receive NF discovery request from NFinstance, provide information about the discovered NF instances (bediscovered) to the NF instance, and maintain information about availableNF instances and their supported services, and/or the like.

In an example, an NSSF 120 may select a set of network slice instancesserving the UE 100, may determine allowed NSSAI. In an example, the NSSF120 may determine the AMF 155 set to be employed to serve the UE 100,and/or, based on configuration, determine a list of candidate AMF 155(s)155 by querying the NRF 130.

In an example, stored data in a UDR may include at least usersubscription data, including at least subscription identifiers, securitycredentials, access and mobility related subscription data, sessionrelated subscription data, policy data, and/or the like.

In an example, an AUSF 150 may support authentication server function(AUSF 150).

In an example, an application function, AF 145, may interact with the3GPP core network to provide services. In an example, based on operatordeployment, application functions may be trusted by the operator tointeract directly with relevant network functions. Application functionsnot allowed by the operator to access directly the network functions mayuse an external exposure framework (e.g., via the NEF 125) to interactwith relevant network functions.

In an example, control plane interface between the (R)AN 105 and the 5Gcore may support connection of multiple different kinds of AN(s) (e.g.3GPP RAN 105, N3IWF 170 for Un-trusted access 165) to the 5GC via acontrol plane protocol. In an example, an N2 AP protocol may be employedfor both the 3GPP access 105 and non-3GPP access 165. In an example,control plane interface between the (R)AN 105 and the 5G core maysupport decoupling between AMF 155 and other functions such as SMF 160that may need to control the services supported by AN(s) (e.g. controlof the UP resources in the AN 105 for a PDU session).

In an example, the 5GC may provide policy information from the PCF 135to the UE 100. In an example, the policy information may comprise:access network discovery and selection policy, UE 100 route selectionpolicy (URSP), SSC mode selection policy (SSCMSP), network sliceselection policy (NSSP), DNN selection policy, non-seamless offloadpolicy, and/or the like.

In an example, as depicted in example FIG. 5A and FIG. 5B, theregistration management, RM may be employed to register or de-register aUE/user 100 with the network, and establish the user context in thenetwork. Connection management may be employed to establish and releasethe signaling connection between the UE 100 and the AMF 155.

In an example, a UE 100 may register with the network to receiveservices that require registration. In an example, the UE 100 may updateits registration with the network periodically in order to remainreachable (periodic registration update), or upon mobility (e.g.,mobility registration update), or to update its capabilities or tore-negotiate protocol parameters.

In an example, an initial registration procedure as depicted in exampleFIG. 8 and FIG. 9 may involve execution of network access controlfunctions (e.g. user authentication and access authorization based onsubscription profiles in UDM 140). Example FIG. 9 is a continuation ofthe initial registration procedure depicted in FIG. 8 . As a result ofthe initial registration procedure, the identity of the serving AMF 155may be registered in a UDM 140.

In an example, the registration management, RM procedures may beapplicable over both 3GPP access 105 and non 3GPP access 165.

An example FIG. 5A may depict the RM states of a UE 100 as observed bythe UE 100 and AMF 155. In an example embodiment, two RM states may beemployed in the UE 100 and the AMF 155 that may reflect the registrationstatus of the UE 100 in the selected PLMN: RM-DEREGISTERED 500, andRM-REGISTERED 510. In an example, in the RM DEREGISTERED state 500, theUE 100 may not be registered with the network. The UE 100 context in theAMF 155 may not hold valid location or routing information for the UE100 so the UE 100 may not be reachable by the AMF 155. In an example,the UE 100 context may be stored in the UE 100 and the AMF 155. In anexample, in the RM REGISTERED state 510, the UE 100 may be registeredwith the network. In the RM-REGISTERED 510 state, the UE 100 may receiveservices that may require registration with the network.

In an example embodiment, two RM states may be employed in AMF 155 forthe UE 100 that may reflect the registration status of the UE 100 in theselected PLMN: RM-DEREGISTERED 520, and RM-REGISTERED 530.

As depicted in example FIG. 6A and FIG. 6B, connection management, CM,may comprise establishing and releasing a signaling connection between aUE 100 and an AMF 155 over N1 interface. The signaling connection may beemployed to enable NAS signaling exchange between the UE 100 and thecore network. The signaling connection between the UE 100 and the AMF155 may comprise both the AN signaling connection between the UE 100 andthe (R)AN 105 (e.g. RRC connection over 3GPP access) and the N2connection for the UE 100 between the AN and the AMF 155.

As depicted in example FIG. 6A and FIG. 6B, two CM states may beemployed for the NAS signaling connectivity of the UE 100 with the AMF155, CM-IDLE 600, 620 and CM-CONNECTED 610, 630. A UE 100 in CM-IDLE 600state may be in RM-REGISTERED 510 state and may have no NAS signalingconnection established with the AMF 155 over N1. The UE 100 may performcell selection, cell reselection, PLMN selection, and/or the like. A UE100 in CM-CONNECTED 610 state may have a NAS signaling connection withthe AMF 155 over N1.

In an example embodiment two CM states may be employed for the UE 100 atthe AMF 155, CM-IDLE 620 and CM-CONNECTED 630.

In an example, an RRC inactive state may apply to NG-RAN (e.g. it mayapply to NR and E-UTRA connected to 5G CN). The AMF 155, based onnetwork configuration, may provide assistance information to the NG RAN105, to assist the NG RAN's 105 decision whether the UE 100 may be sentto RRC inactive state. When a UE 100 is CM-CONNECTED 610 with RRCinactive state, the UE 100 may resume the RRC connection due to uplinkdata pending, mobile initiated signaling procedure, as a response to RAN105 paging, to notify the network that it has left the RAN 105notification area, and/or the like.

In an example, a NAS signaling connection management may includeestablishing and releasing a NAS signaling connection. A NAS signalingconnection establishment function may be provided by the UE 100 and theAMF 155 to establish the NAS signaling connection for the UE 100 inCM-IDLE 600 state. The procedure of releasing the NAS signalingconnection may be initiated by the 5G (R)AN 105 node or the AMF 155.

In an example, reachability management of a UE 100 may detect whetherthe UE 100 is reachable and may provide the UE 100 location (e.g. accessnode) to the network to reach the UE 100. Reachability management may bedone by paging the UE 100 and the UE 100 location tracking. The UE 100location tracking may include both UE 100 registration area tracking andUE 100 reachability tracking. The UE 100 and the AMF 155 may negotiateUE 100 reachability characteristics in CM-IDLE 600, 620 state duringregistration and registration update procedures.

In an example, two UE 100 reachability categories may be negotiatedbetween a UE 100 and an AMF 155 for CM-IDLE 600, 620 state. 1) UE 100reachability allowing mobile device terminated data while the UE 100 isCM-IDLE 600 mode. 2) Mobile initiated connection only (MICO) mode. The5GC may support a PDU connectivity service that provides exchange ofPDUs between the UE 100 and a data network identified by a DNN. The PDUconnectivity service may be supported via PDU sessions that areestablished upon request from the UE 100.

In an example, a PDU session may support one or more PDU session types.PDU sessions may be established (e.g. upon UE 100 request), modified(e.g. upon UE 100 and 5GC request) and/or released (e.g. upon UE 100 and5GC request) using NAS SM signaling exchanged over N1 between the UE 100and the SMF 160. Upon request from an application server, the 5GC may beable to trigger a specific application in the UE 100. When receiving thetrigger, the UE 100 may send it to the identified application in the UE100. The identified application in the UE 100 may establish a PDUsession to a specific DNN.

In an example, the 5G QoS model may support a QoS flow based frameworkas depicted in example FIG. 7 . The 5G QoS model may support both QoSflows that require a guaranteed flow bit rate and QoS flows that may notrequire a guaranteed flow bit rate. In an example, the 5G QoS model maysupport reflective QoS. The QoS model may comprise flow mapping orpacket marking at the UPF 110 (CN_UP) 110, AN 105 and/or the UE 100. Inan example, packets may arrive from and/or destined to theapplication/service layer 730 of UE 100, UPF 110 (CN_UP) 110, and/or theAF 145.

In an example, the QoS flow may be a granularity of QoS differentiationin a PDU session. A QoS flow ID, QFI, may be employed to identify theQoS flow in the 5G system. In an example, user plane traffic with thesame QFI within a PDU session may receive the same traffic forwardingtreatment. The QFI may be carried in an encapsulation header on N3and/or N9 (e.g. without any changes to the end-to-end packet header). Inan example, the QFI may be applied to PDUs with different types ofpayload. The QFI may be unique within a PDU session.

In an example, the QoS parameters of a QoS flow may be provided to the(R)AN 105 as a QoS profile over N2 at PDU session establishment, QoSflow establishment, or when NG-RAN is used at every time the user planeis activated. In an example, a default QoS rule may be required forevery PDU session. The SMF 160 may allocate the QFI for a QoS flow andmay derive QoS parameters from the information provided by the PCF 135.In an example, the SMF 160 may provide the QFI together with the QoSprofile containing the QoS parameters of a QoS flow to the (R)AN 105.

In an example, 5G QoS flow may be a granularity for QoS forwardingtreatment in the 5G system. Traffic mapped to the same 5G QoS flow mayreceive the same forwarding treatment (e.g. scheduling policy, queuemanagement policy, rate shaping policy, RLC configuration, and/or thelike). In an example, providing different QoS forwarding treatment mayrequire separate 5G QoS flows.

In an example, a 5G QoS indicator may be a scalar that may be employedas a reference to a specific QoS forwarding behavior (e.g. packet lossrate, packet delay budget) to be provided to a 5G QoS flow. In anexample, the 5G QoS indicator may be implemented in the access networkby the 5QI referencing node specific parameters that may control the QoSforwarding treatment (e.g. scheduling weights, admission thresholds,queue management thresholds, link layer protocol configuration, and/orthe like).

In an example, 5GC may support edge computing and may enable operator(s)and 3rd party services to be hosted close to the UE's access point ofattachment. The 5G core network may select a UPF 110 close to the UE 100and may execute the traffic steering from the UPF 110 to the local datanetwork via a N6 interface. In an example, the selection and trafficsteering may be based on the UE's 100 subscription data, UE 100location, the information from application function AF 145, policy,other related traffic rules, and/or the like. In an example, the 5G corenetwork may expose network information and capabilities to an edgecomputing application function. The functionality support for edgecomputing may include local routing where the 5G core network may selecta UPF 110 to route the user traffic to the local data network, trafficsteering where the 5G core network may select the traffic to be routedto the applications in the local data network, session and servicecontinuity to enable UE 100 and application mobility, user planeselection and reselection, e.g. based on input from applicationfunction, network capability exposure where 5G core network andapplication function may provide information to each other via NEF 125,QoS and charging where PCF 135 may provide rules for QoS control andcharging for the traffic routed to the local data network, support oflocal area data network where 5G core network may provide support toconnect to the LADN in a certain area where the applications aredeployed, and/or the like.

An example 5G system may be a 3GPP system comprising of 5G accessnetwork 105, 5G core network and a UE 100, and/or the like. AllowedNSSAI may be an NSSAI provided by a serving PLMN during e.g. aregistration procedure, indicating the NSSAI allowed by the network forthe UE 100 in the serving PLMN for the current registration area.

In an example, a PDU connectivity service may provide exchange of PDUsbetween a UE 100 and a data network. A PDU session may be an associationbetween the UE 100 and the data network, DN 115, that may provide thePDU connectivity service. The type of association may be IP, Ethernetand/or unstructured.

Establishment of user plane connectivity to a data network via networkslice instance(s) may comprise the following: performing a RM procedureto select an AMF 155 that supports the required network slices, andestablishing one or more PDU session(s) to the required data network viathe network slice instance(s).

In an example, the set of network slices for a UE 100 may be changed atany time while the UE 100 may be registered with the network, and may beinitiated by the network, or the UE 100.

In an example, a periodic registration update may be UE 100re-registration at expiry of a periodic registration timer. A requestedNSSAI may be a NSSAI that the UE 100 may provide to the network.

In an example, a service based interface may represent how a set ofservices may be provided/exposed by a given NF.

In an example, a service continuity may be an uninterrupted userexperience of a service, including the cases where the IP address and/oranchoring point may change. In an example, a session continuity mayrefer to continuity of a PDU session. For PDU session of IP type sessioncontinuity may imply that the IP address is preserved for the lifetimeof the PDU session. An uplink classifier may be a UPF 110 functionalitythat aims at diverting uplink traffic, based on filter rules provided bythe SMF 160, towards data network, DN 115.

In an example, the 5G system architecture may support data connectivityand services enabling deployments to use techniques such as e.g. networkfunction virtualization and/or software defined networking. The 5Gsystem architecture may leverage service-based interactions betweencontrol plane (CP) network functions where identified. In 5G systemarchitecture, separation of the user plane (UP) functions from thecontrol plane functions may be considered. A 5G system may enable anetwork function to interact with other NF(s) directly if required.

In an example, the 5G system may reduce dependencies between the accessnetwork (AN) and the core network (CN). The architecture may comprise aconverged access-agnostic core network with a common AN-CN interfacewhich may integrate different 3GPP and non-3GPP access types.

In an example, the 5G system may support a unified authenticationframework, stateless NFs, where the compute resource is decoupled fromthe storage resource, capability exposure, and concurrent access tolocal and centralized services. To support low latency services andaccess to local data networks, UP functions may be deployed close to theaccess network.

In an example, the 5G system may support roaming with home routedtraffic and/or local breakout traffic in the visited PLMN. An example 5Garchitecture may be service-based and the interaction between networkfunctions may be represented in two ways. (1) As service-basedrepresentation (depicted in example FIG. 1 ), where network functionswithin the control plane, may enable other authorized network functionsto access their services. This representation may also includepoint-to-point reference points where necessary. (2) Reference pointrepresentation, showing the interaction between the NF services in thenetwork functions described by point-to-point reference point (e.g. N11)between any two network functions.

In an example, a network slice may comprise the core network controlplane and user plane network functions, the 5G Radio Access Network; theN3IWF functions to the non-3GPP Access Network, and/or the like. Networkslices may differ for supported features and network functionimplementation. The operator may deploy multiple network slice instancesdelivering the same features but for different groups of UEs, e.g. asthey deliver a different committed service and/or because they may bededicated to a customer. The NSSF 120 may store the mapping informationbetween slice instance ID and NF ID (or NF address).

In an example, a UE 100 may simultaneously be served by one or morenetwork slice instances via a 5G-AN. In an example, the UE 100 may beserved by k network slices (e.g. k=8, 16, etc.) at a time. An AMF 155instance serving the UE 100 logically may belong to a network sliceinstance serving the UE 100.

In an example, a PDU session may belong to one specific network sliceinstance per PLMN. In an example, different network slice instances maynot share a PDU session. Different slices may have slice-specific PDUsessions using the same DNN.

An S-NSSAI (Single Network Slice Selection Assistance information) mayidentify a network slice. An S-NSSAI may comprise a slice/service type(SST), which may refer to the expected network slice behavior in termsof features and services; and/or a slice differentiator (SD). A slicedifferentiator may be optional information that may complement theslice/service type(s) to allow further differentiation for selecting anetwork slice instance from potentially multiple network slice instancesthat comply with the indicated slice/service type. In an example, thesame network slice instance may be selected employing differentS-NSSAIs. The CN part of a network slice instance(s) serving a UE 100may be selected by CN.

In an example, subscription data may include the S-NSSAI(s) of thenetwork slices that the UE 100 subscribes to. One or more S-NSSAIs maybe marked as default S-NSSAI. In an example, k S-NSSAI may be markeddefault S-NSSAI (e.g. k=8, 16, etc.). In an example, the UE 100 maysubscribe to more than 8 S-NSSAIs.

In an example, a UE 100 may be configured by the HPLMN with a configuredNSSAI per PLMN. Upon successful completion of a UE's registrationprocedure, the UE 100 may obtain from the AMF 155 an Allowed NSSAI forthis PLMN, which may include one or more S-NSSAIs.

In an example, the Allowed NSSAI may take precedence over the configuredNSSAI for a PLMN. The UE 100 may use the S-NSSAIs in the allowed NSSAIcorresponding to a network slice for the subsequent network sliceselection related procedures in the serving PLMN.

In an example, the establishment of user plane connectivity to a datanetwork via a network slice instance(s) may comprise: performing a RMprocedure to select an AMF 155 that may support the required networkslices, establishing one or more PDU sessions to the required datanetwork via the network slice instance(s), and/or the like.

In an example, when a UE 100 registers with a PLMN, if the UE 100 forthe PLMN has a configured NSSAI or an allowed NSSAI, the UE 100 mayprovide to the network in RRC and NAS layer a requested NSSAI comprisingthe S-NSSAI(s) corresponding to the slice(s) to which the UE 100attempts to register, a temporary user ID if one was assigned to the UE,and/or the like. The requested NSSAI may be configured-NSSAI,allowed-NSSAI, and/or the like.

In an example, when a UE 100 registers with a PLMN, if for the PLMN theUE 100 has no configured NSSAI or allowed NSSAI, the RAN 105 may routeNAS signaling from/to the UE 100 to/from a default AMF 155.

In an example, the network, based on local policies, subscriptionchanges and/or UE 100 mobility, may change the set of permitted networkslice(s) to which the UE 100 is registered. In an example, the networkmay perform the change during a registration procedure or trigger anotification towards the UE 100 of the change of the supported networkslices using an RM procedure (which may trigger a registrationprocedure). The network may provide the UE 100 with a new allowed NSSAIand tracking area list.

In an example, during a registration procedure in a PLMN, in case thenetwork decides that the UE 100 should be served by a different AMF 155based on network slice(s) aspects, the AMF 155 that first received theregistration request may redirect the registration request to anotherAMF 155 via the RAN 105 or via direct signaling between the initial AMF155 and the target AMF 155.

In an example, the network operator may provision the UE 100 withnetwork slice selection policy (NSSP). The NSSP may comprise one or moreNSSP rules.

In an example, if a UE 100 has one or more PDU sessions establishedcorresponding to a specific S-NSSAI, the UE 100 may route the user dataof the application in one of the PDU sessions, unless other conditionsin the UE 100 may prohibit the use of the PDU sessions. If theapplication provides a DNN, then the UE 100 may consider the DNN todetermine which PDU session to use. In an example, if the UE 100 doesnot have a PDU session established with the specific S-NSSAI, the UE 100may request a new PDU session corresponding to the S-NSSAI and with theDNN that may be provided by the application. In an example, in order forthe RAN 105 to select a proper resource for supporting network slicingin the RAN 105, the RAN 105 may be aware of the network slices used bythe UE 100.

In an example, an AMF 155 may select an SMF 160 in a network sliceinstance based on S-NSSAI, DNN and/or other information e.g. UE 100subscription and local operator policies, and/or the like, when the UE100 triggers the establishment of a PDU session. The selected SMF 160may establish the PDU session based on S-NSSAI and DNN.

In an example, in order to support network-controlled privacy of sliceinformation for the slices the UE 100 may access, when the UE 100 isaware or configured that privacy considerations may apply to NSSAI, theUE 100 may not include NSSAI in NAS signaling unless the UE 100 has aNAS security context and the UE 100 may not include NSSAI in unprotectedRRC signaling.

In an example, for roaming scenarios, the network slice specific networkfunctions in VPLMN and HPLMN may be selected based on the S-NSSAIprovided by the UE 100 during PDU connection establishment. If astandardized S-NSSAI is used, selection of slice specific NF instancesmay be done by each PLMN based on the provided S-NSSAI. In an example,the VPLMN may map the S-NSSAI of HPLMN to a S-NSSAI of VPLMN based onroaming agreement (e.g., including mapping to a default S-NSSAI ofVPLMN). In an example, the selection of slice specific NF instance inVPLMN may be done based on the S-NSSAI of VPLMN. In an example, theselection of any slice specific NF instance in HPLMN may be based on theS-NSSAI of HPLMN.

As depicted in example FIG. 8 and FIG. 9 , a registration procedure maybe performed by the UE 100 to get authorized to receive services, toenable mobility tracking, to enable reachability, and/or the like.

In an example, the UE 100 may send to the (R)AN 105 an AN message(comprising AN parameters, RM-NAS registration request (registrationtype, SUCI or SUPI or 5G-GUTI, last visited TAI (if available), securityparameters, requested NSSAI, mapping of requested NSSAI, UE 100 5GCcapability, PDU session status, PDU session(s) to be re-activated,Follow on request, MICO mode preference, and/or the like), and/or thelike). In an example, in case of NG-RAN, the AN parameters may includee.g. SUCI or SUPI or the 5G-GUTI, the Selected PLMN ID and requestedNSSAI, and/or the like. In an example, the AN parameters may compriseestablishment cause. The establishment cause may provide the reason forrequesting the establishment of an RRC connection. In an example, theregistration type may indicate if the UE 100 wants to perform an initialregistration (i.e. the UE 100 is in RM-DEREGISTERED state), a mobilityregistration update (e.g., the UE 100 is in RM-REGISTERED state andinitiates a registration procedure due to mobility), a periodicregistration update (e.g., the UE 100 is in RM-REGISTERED state and mayinitiate a registration procedure due to the periodic registrationupdate timer expiry) or an emergency registration (e.g., the UE 100 isin limited service state). In an example, if the UE 100 performing aninitial registration (i.e., the UE 100 is in RM-DEREGISTERED state) to aPLMN for which the UE 100 does not already have a 5G-GUTI, the UE 100may include its SUCI or SUPI in the registration request. The SUCI maybe included if the home network has provisioned the public key toprotect SUPI in the UE. If the UE 100 received a UE 100 configurationupdate command indicating that the UE 100 needs to re-register and the5G-GUTI is invalid, the UE 100 may perform an initial registration andmay include the SUPI in the registration request message. For anemergency registration, the SUPI may be included if the UE 100 does nothave a valid 5G-GUTI available; the PEI may be included when the UE 100has no SUPI and no valid 5G-GUTI. In other cases, the 5G-GUTI may beincluded and it may indicate the last serving AMF 155. If the UE 100 isalready registered via a non-3GPP access in a PLMN different from thenew PLMN (e.g., not the registered PLMN or an equivalent PLMN of theregistered PLMN) of the 3GPP access, the UE 100 may not provide over the3GPP access the 5G-GUTI allocated by the AMF 155 during the registrationprocedure over the non-3GPP access. If the UE 100 is already registeredvia a 3GPP access in a PLMN (e.g., the registered PLMN), different fromthe new PLMN (i.e. not the registered PLMN or an equivalent PLMN of theregistered PLMN) of the non-3GPP access, the UE 100 may not provide overthe non-3GPP access the 5G-GUTI allocated by the AMF 155 during theregistration procedure over the 3GPP access. The UE 100 may provide theUE's usage setting based on its configuration. In case of initialregistration or mobility registration update, the UE 100 may include themapping of requested NSSAI, which may be the mapping of each S-NSSAI ofthe requested NSSAI to the S-NSSAIs of the configured NSSAI for theHPLMN, to ensure that the network is able to verify whether theS-NSSAI(s) in the requested NSSAI are permitted based on the subscribedS-NSSAIs. If available, the last visited TAI may be included in order tohelp the AMF 155 produce registration area for the UE. In an example,the security parameters may be used for authentication and integrityprotection, requested NSSAI may indicate the network slice selectionassistance information. The PDU session status may indicates thepreviously established PDU sessions in the UE. When the UE 100 isconnected to the two AMF 155 belonging to different PLMN via 3GPP accessand non-3GPP access then the PDU session status may indicate theestablished PDU session of the current PLMN in the UE. The PDUsession(s) to be re-activated may be included to indicate the PDUsession(s) for which the UE 100 may intend to activate UP connections. APDU session corresponding to a LADN may not be included in the PDUsession(s) to be re-activated when the UE 100 is outside the area ofavailability of the LADN. The follow on request may be included when theUE 100 may have pending uplink signaling and the UE 100 may not includePDU session(s) to be re-activated, or the registration type may indicatethe UE 100 may want to perform an emergency registration.

In an example, if a SUPI is included or the 5G-GUTI does not indicate avalid AMF 155, the (R)AN 105, based on (R)AT and requested NSSAI, ifavailable, may selects 808 an AMF 155. If UE 100 is in CM-CONNECTEDstate, the (R)AN 105 may forward the registration request message to theAMF 155 based on the N2 connection of the UE. If the (R)AN 105 may notselect an appropriate AMF 155, it may forward the registration requestto an AMF 155 which has been configured, in (R)AN 105, to perform AMF155 selection 808.

In an example, the (R)AN 105 may send to the new AMF 155 an N2 message(comprising: N2 parameters, RM-NAS registration request (registrationtype, SUPI or 5G-GUTI, last visited TAI (if available), securityparameters, requested NSSAI, mapping of requested NSSAI, UE 100 5GCcapability, PDU session status, PDU session(s) to be re-activated,follow on request, and MICO mode preference), and/or the like). In anexample, when NG-RAN is used, the N2 parameters may comprise theselected PLMN ID, location information, cell identity and the RAT typerelated to the cell in which the UE 100 is camping. In an example, whenNG-RAN is used, the N2 parameters may include the establishment cause.

In an example, the new AMF 155 may send to the old AMF 155 anNamf_Communication_UEContextTransfer (complete registration request). Inan example, if the UE's 5G-GUTI was included in the registration requestand the serving AMF 155 has changed since last registration procedure,the new AMF 155 may invoke the Namf_Communication_UEContextTransferservice operation on the old AMF 155 including the complete registrationrequest IE, which may be integrity protected, to request the UE's SUPIand MM Context. The old AMF 155 may use the integrity protected completeregistration request IE to verify if the context transfer serviceoperation invocation corresponds to the UE 100 requested. In an example,the old AMF 155 may transfer the event subscriptions information by eachNF consumer, for the UE, to the new AMF 155. In an example, if the UE100 identifies itself with PEI, the SUPI request may be skipped.

In an example, the old AMF 155 may send to new AMF 155 a response toNamf_Communication_UEContextTransfer (SUPI, MM context, SMF 160information, PCF ID). In an example, the old AMF 155 may respond to thenew AMF 155 for the Namf_Communication_UEContextTransfer invocation byincluding the UE's SUPI and MM context. In an example, if old AMF 155holds information about established PDU sessions, the old AMF 155 mayinclude SMF 160 information including S-NSSAI(s), SMF 160 identities andPDU session ID. In an example, if old AMF 155 holds information aboutactive NGAP UE-TNLA bindings to N3IWF, the old AMF 155 may includeinformation about the NGAP UE-TNLA bindings.

In an example, if the SUPI is not provided by the UE 100 nor retrievedfrom the old AMF 155 the identity request procedure may be initiated bythe AMF 155 sending an identity request message to the UE 100 requestingthe SUCI.

In an example, the UE 100 may respond with an identity response messageincluding the SUCI. The UE 100 may derive the SUCI by using theprovisioned public key of the HPLMN.

In an example, the AMF 155 may decide to initiate UE 100 authenticationby invoking an AUSF 150. The AMF 155 may select an AUSF 150 based onSUPI or SUCI. In an example, if the AMF 155 is configured to supportemergency registration for unauthenticated SUPIs and the UE 100indicated registration type emergency registration, the AMF 155 may skipthe authentication and security setup, or the AMF 155 may accept thatthe authentication may fail and may continue the registration procedure.

In an example, the authentication may be performed byNudm_UEAuthenticate_Get operation. The AUSF 150 may discover a UDM 140.In case the AMF 155 provided a SUCI to AUSF 150, the AUSF 150 may returnthe SUPI to AMF 155 after the authentication is successful. In anexample, if network slicing is used, the AMF 155 may decide if theregistration request needs to be rerouted where the initial AMF 155refers to the AMF 155. In an example, the AMF 155 may initiate NASsecurity functions. In an example, upon completion of NAS securityfunction setup, the AMF 155 may initiate NGAP procedure to enable 5G-ANuse it for securing procedures with the UE. In an example, the 5G-AN maystore the security context and may acknowledge to the AMF 155. The 5G-ANmay use the security context to protect the messages exchanged with theUE.

In an example, new AMF 155 may send to the old AMF 155Namf_Communication_RegistrationCompleteNotify. If the AMF 155 haschanged, the new AMF 155 may notify the old AMF 155 that theregistration of the UE 100 in the new AMF 155 may be completed byinvoking the Namf_Communication_RegistrationCompleteNotify serviceoperation. If the authentication/security procedure fails, then theregistration may be rejected, and the new AMF 155 may invoke theNamf_Communication_RegistrationCompleteNotify service operation with areject indication reason code towards the old AMF 155. The old AMF 155may continue as if the UE 100 context transfer service operation wasnever received. If one or more of the S-NSSAIs used in the oldregistration area may not be served in the target registration area, thenew AMF 155 may determine which PDU session may not be supported in thenew registration area. The new AMF 155 may invoke theNamf_Communication_RegistrationCompleteNotify service operationincluding the rejected PDU session ID and a reject cause (e.g. theS-NSSAI becomes no longer available) towards the old AMF 155. The newAMF 155 may modify the PDU session status correspondingly. The old AMF155 may inform the corresponding SMF 160(s) to locally release the UE'sSM context by invoking the Nsmf_PDUSession_ReleaseSMContext serviceoperation.

In an example, the new AMF 155 may send to the UE 100 an identityrequest/response (e.g., PEI). If the PEI was not provided by the UE 100nor retrieved from the old AMF 155, the identity request procedure maybe initiated by AMF 155 sending an identity request message to the UE100 to retrieve the PEI. The PEI may be transferred encrypted unless theUE 100 performs emergency registration and may not be authenticated. Foran emergency registration, the UE 100 may have included the PEI in theregistration request.

In an example, the new AMF 155 may initiate ME identity check byinvoking the N5g-eir_EquipmentIdentityCheck_Get service operation.

In an example, the new AMF 155, based on the SUPI, may select a UDM 140.The UDM 140 may select a UDR instance. In an example, the AMF 155 mayselect a UDM 140.

In an example, if the AMF 155 has changed since the last registrationprocedure, or if the UE 100 provides a SUPI which may not refer to avalid context in the AMF 155, or if the UE 100 registers to the same AMF155 it has already registered to a non-3GPP access (e.g., the UE 100 isregistered over a non-3GPP access and may initiate the registrationprocedure to add a 3GPP access), the new AMF 155 may register with theUDM 140 using Nudm_UECM_Registration and may subscribe to be notifiedwhen the UDM 140 may deregister the AMF 155. The UDM 140 may store theAMF 155 identity associated to the access type and may not remove theAMF 155 identity associated to the other access type. The UDM 140 maystore information provided at registration in UDR, by Nudr_UDM_Update.In an example, the AMF 155 may retrieve the access and mobilitysubscription data and SMF 160 selection subscription data usingNudm_SDM_Get. The UDM 140 may retrieve this information from UDR byNudr_UDM_Query (access and mobility subscription data). After asuccessful response is received, the AMF 155 may subscribe to benotified using Nudm_SDM_Subscribe when the data requested may bemodified. The UDM 140 may subscribe to UDR by Nudr_UDM_Subscribe. TheGPSI may be provided to the AMF 155 in the subscription data from theUDM 140 if the GPSI is available in the UE 100 subscription data. In anexample, the new AMF 155 may provide the access type it serves for theUE 100 to the UDM 140 and the access type may be set to 3GPP access. TheUDM 140 may store the associated access type together with the servingAMF 155 in UDR by Nudr_UDM_Update. The new AMF 155 may create an MMcontext for the UE 100 after getting the mobility subscription data fromthe UDM 140. In an example, when the UDM 140 stores the associatedaccess type together with the serving AMF 155, the UDM 140 may initiatea Nudm_UECM_DeregistrationNotification to the old AMF 155 correspondingto 3GPP access. The old AMF 155 may remove the MM context of the UE. Ifthe serving NF removal reason indicated by the UDM 140 is initialregistration, then the old AMF 155 may invoke theNamf_EventExposure_Notify service operation towards all the associatedSMF 160 s of the UE 100 to notify that the UE 100 is deregistered fromold AMF 155. The SMF 160 may release the PDU session(s) on getting thisnotification. In an example, the old AMF 155 may unsubscribe with theUDM 140 for subscription data using Nudm_SDM_unsubscribe.

In an example, if the AMF 155 decides to initiate PCF 135 communication,e.g. the AMF 155 has not yet obtained access and mobility policy for theUE 100 or if the access and mobility policy in the AMF 155 are no longervalid, the AMF 155 may select a PCF 135. If the new AMF 155 receives aPCF ID from the old AMF 155 and successfully contacts the PCF 135identified by the PCF ID, the AMF 155 may select the (V-)PCF identifiedby the PCF ID. If the PCF 135 identified by the PCF ID may not be used(e.g. no response from the PCF 135) or if there is no PCF ID receivedfrom the old AMF 155, the AMF 155 may select a PCF 135.

In an example, the new AMF 155 may perform a policy associationestablishment during registration procedure. If the new AMF 155 contactsthe PCF 135 identified by the (V-)PCF ID received during inter-AMF 155mobility, the new AMF 155 may include the PCF-ID in theNpcf_AMPolicyControl_Get operation. If the AMF 155 notifies the mobilityrestrictions (e.g. UE 100 location) to the PCF 135 for adjustment, or ifthe PCF 135 updates the mobility restrictions itself due to someconditions (e.g. application in use, time and date), the PCF 135 mayprovide the updated mobility restrictions to the AMF 155.

In an example, the PCF 135 may invoke Namf_EventExposure_Subscribeservice operation for UE 100 event subscription.

In an example, the AMF 155 may send to the SMF 160 anNsmf_PDUSession_UpdateSMContext. In an example, the AMF 155 may invokethe Nsmf_PDUSession_UpdateSMContext if the PDU session(s) to bere-activated is included in the registration request. The AMF 155 maysend Nsmf_PDUSession_UpdateSMContext request to SMF 160(s) associatedwith the PDU session(s) to activate user plane connections of the PDUsession(s). The SMF 160 may decide to trigger e.g. the intermediate UPF110 insertion, removal or change of PSA. In the case that theintermediate UPF 110 insertion, removal, or relocation is performed forthe PDU session(s) not included in PDU session(s) to be re-activated,the procedure may be performed without N11 and N2 interactions to updatethe N3 user plane between (R)AN 105 and 5GC. The AMF 155 may invoke theNsmf_PDUSession_ReleaseSMContext service operation towards the SMF 160if any PDU session status indicates that it is released at the UE 100.The AMF 155 may invoke the Nsmf_PDUSession_ReleaseSMContext serviceoperation towards the SMF 160 in order to release any network resourcesrelated to the PDU session.

In an example, the new AMF 155 may send to a N3IWF an N2 AMF 155mobility request. If the AMF 155 has changed, the new AMF 155 may createan NGAP UE 100 association towards the N3IWF to which the UE 100 isconnected. In an example, the N3IWF may respond to the new AMF 155 withan N2 AMF 155 mobility response.

In an example, the new AMF 155 may send to the UE 100 a registrationaccept (comprising: 5G-GUTI, registration area, mobility restrictions,PDU session status, allowed NSSAI, [mapping of allowed NSSAI], periodicregistration update timer, LADN information and accepted MICO mode, IMSvoice over PS session supported indication, emergency service supportindicator, and/or the like). In an example, the AMF 155 may send theregistration accept message to the UE 100 indicating that theregistration request has been accepted. 5G-GUTI may be included if theAMF 155 allocates a new 5G-GUTI. If the AMF 155 allocates a newregistration area, it may send the registration area to the UE 100 viaregistration accept message. If there is no registration area includedin the registration accept message, the UE 100 may consider the oldregistration area as valid. In an example, mobility restrictions may beincluded in case mobility restrictions may apply for the UE 100 andregistration type may not be emergency registration. The AMF 155 mayindicate the established PDU sessions to the UE 100 in the PDU sessionstatus. The UE 100 may remove locally any internal resources related toPDU sessions that are not marked as established in the received PDUsession status. In an example, when the UE 100 is connected to the twoAMF 155 belonging to different PLMN via 3GPP access and non-3GPP accessthen the UE 100 may remove locally any internal resources related to thePDU session of the current PLMN that are not marked as established inreceived PDU session status. If the PDU session status information wasin the registration request, the AMF 155 may indicate the PDU sessionstatus to the UE. The mapping of allowed NSSAI may be the mapping ofeach S-NSSAI of the allowed NSSAI to the S-NSSAIs of the configuredNSSAI for the HPLMN. The AMF 155 may include in the registration acceptmessage the LADN information for LADNs that are available within theregistration area determined by the AMF 155 for the UE. If the UE 100included MICO mode in the request, then AMF 155 may respond whether MICOmode may be used. The AMF 155 may set the IMS voice over PS sessionsupported Indication. In an example, in order to set the IMS voice overPS session supported indication, the AMF 155 may perform a UE/RAN radioinformation and compatibility request procedure to check thecompatibility of the UE 100 and RAN radio capabilities related to IMSvoice over PS. In an example, the emergency service support indicatormay inform the UE 100 that emergency services are supported, e.g., theUE 100 may request PDU session for emergency services. In an example,the handover restriction list and UE-AMBR may be provided to NG-RAN bythe AMF 155.

In an example, the UE 100 may send to the new AMF 155 a registrationcomplete message. In an example, the UE 100 may send the registrationcomplete message to the AMF 155 to acknowledge that a new 5G-GUTI may beassigned. In an example, when information about the PDU session(s) to bere-activated is not included in the registration request, the AMF 155may release the signaling connection with the UE 100. In an example,when the follow-on request is included in the registration request, theAMF 155 may not release the signaling connection after the completion ofthe registration procedure. In an example, if the AMF 155 is aware thatsome signaling is pending in the AMF 155 or between the UE 100 and the5GC, the AMF 155 may not release the signaling connection after thecompletion of the registration procedure.

In an example, FIG. 10 is a diagram of 5G policy and charging controlsystem architecture. The reference architecture of policy and chargingcontrol framework for the 5G system may comprise one or more of thefollowing network functions: policy control function (PCF), sessionmanagement function (SMF), user plane function (UPF), access andmobility management function (AMF), network exposure functionality(NEF), network data analytics function (NWDAF), charging function (CHF),application function (AF) and unified data repository (UDR).

As an example, the CHF may support at least one charging method: offlinecharging, online charging, or converged charging.

As an example, the offline charging may be a process where charginginformation for network resource usage may be collected concurrentlywith that resource usage. At the end of the process, CDR files may begenerated by the network, which may be transferred to a networkoperator's billing domain (BD) for the purpose of subscriber billingand/or inter-operator accounting (or additional functions, e.g.statistics, at the operator's discretion). The BD typically comprisespost-processing systems such as the operator's billing system or billingmediation device. As an example conclusion, offline charging may be amechanism where charging information does not affect, in real-time, theservice rendered.

As an example, online charging may be a process where charginginformation for network resource usage may be collected concurrentlywith that resource usage in the same fashion as in offline charging.However, authorization for the network resource usage may be obtained bythe network prior to the actual resource usage to occur. As an example,the charging information utilized in online charging may be notnecessarily identical to the charging information employed in offlinecharging. As an example conclusion, online charging may be a mechanismwhere charging information may affect, in real-time, the servicerendered and therefore a direct interaction of the charging mechanismwith the control of network resource usage may be required.

As an example, converged charging may be a process where online andoffline charging may be combined.

FIG. 11 is an example call flow for PDU session establishment chargingas per an aspect of an embodiment of the present disclosure.

In an example, a UE may initiate a PDU Session establishment procedurecomprising one or more of: PDU Session ID, PDU Type, SSC mode, Userlocation information and Access Technology Type Information.

In response to the message received from the UE, an AMF may select anSMF and send to the selected SMF a message (e.g.Namf_PDUSession_CreateSMContext Request), the SMF may send to the AMF aresponse message (e.g. Namf_PDUSession_CreateSMContext Response).

In an example, the SMF may select a PCF and send to the PCF a message(e.g. SM Policy Association Establishment Request) to request PCC rules,and the PCF may provide PCC rules in a response message (e.g. SM PolicyAssociation Establishment response).

In an example, the SMF may create a Charging Id for the PDU session andmay send a Charging Data Request[initial] message to a CHF forauthorization for the subscriber to start the PDU session which istriggered by start of PDU session charging event.

In an example, the CHF may open CDR for this PDU session and mayacknowledge by sending Charging Data Response [Initial] to the SMF.

In an example, the SMF select a UPF and may initiate an N4 SessionEstablishment/Modification procedure with the selected UPF.

The SMF may interact with the AMF, in an example, the SMF may send tothe AMF a Namf_Communication_N1N2MessageTransfer message comprising oneor more of: PDU Session ID, QoS Profile(s), CN Tunnel Info, and S-NSSAIfrom the Allowed NSSAI.

In an example, the AMF may interact with (R)AN and UE by sending to the(R)AN a N2 PDU Session Request message comprising the informationreceived from the SMF, indicating the PDU session establishment isaccepted.

In an example, the (R)AN may send to the AMF a N2 PDU Session Responsemessage comprising one or more of: PDU Session ID, N2 SM information(PDU Session ID, AN Tunnel Info, List of accepted/rejected QFI(s)),wherein the AN Tunnel Info may be corresponding to the Access Networkaddress of the N3 tunnel corresponding to the PDU Session.

In an example, the AMF may send to the SMF aNsmf_PDUSession_UpdateSMContext Request message comprising the N2 SMinformation received from (R)AN to the SMF.

In an example, the SMF may initiate an N4 Session Modification procedurewith the UPF. The SMF may provide AN Tunnel Info to the UPF as well asthe corresponding forwarding rules. The UPF may send to the SMF aresponse message.

In an example, the SMF may request quota from CHF, e.g. “start ofservice data flow” event may need quota from CHF. The SMF may send amessage to the CHF (e.g. Charging Data Request [update]). As an example,for online charging or converged charging, the SMF may request quotafrom CHF when allocated quota is consumed or a trigger is met to requesta quota.

As an example, the UPF may report resource usage of a PDU session to theSMF. As an example, the UPF may report resource usage of a wirelessdevice to the SMF, by enforcing the charging control rules, the SMF maysend to the CHF a message (e.g. Charging Data Request [update])comprising resource usage information received from the UPF.

In an example, the CHF may update CDR for this PDU session. The CHF mayacknowledge the SMF by sending a Charging Data Response message.

In an example, the SMF may send to the AMF aNsmf_PDUSession_UpdateSMContext Response message.

In an example, other interactions may be performed between SMF, AMF,(R)AN and UE for the PDU session establishment procedure.

Implementation of the existing technologies may have issues insupporting charging control. The existing technologies may have issuesthat where and how a PCF receive charging related information. Theexisting technologies may have issues that how the PCF select a CHF. Theexisting technologies may have issues that how the CHF determine acharging method (e.g. online charging, offline charging, or convergedcharging). Example embodiments provides the enhanced mechanisms toindicate charging policy information from a CHF to a PCF. Exampleembodiments provides the enhanced mechanisms to indicate charging policyinformation from a network function to a PCF. Example embodimentsprovides the enhanced mechanisms that the PCF makes policy decisionbased on the received charging policy information. Example embodimentsprovides the enhanced mechanisms to indicate charging type from an SMFto a CHF. Example embodiments provides the enhanced mechanisms to selecta CHF by the PCF. Example embodiments provides the enhanced mechanismsthat the CHF determines a charging method.

In existing systems, a PCF may send a charging control rule to an SMF.Implementation of the existing technologies does not provide chargingcontrol information to the PCF to determine charging control rule.Implementation of the existing technologies may have issues that how acharging function (CHF), a PCF and an SMF coordinated rightly. Withimplementation of existing signaling methods, the PCF may not becoordinated with the CHF and may select an improper charging method.Implementation of the existing technologies does not provide flexibilityin configuring various types of charging control by the PCF. CHF mayhave various charging methods, and there is a need to dynamicallycoordinate the charging method between a CHF and a PCF.

Example embodiments provides enhanced mechanisms to coordinate chargingpolicy information between a CHF and a PCF. In an example embodiment, aPCF may make policy decisions based on received charging policyinformation from a CHF. Example embodiments provides an enhanced methodin configuring various types of charging control by the PCF. Exampleembodiments provides an enhanced method to select a proper chargingmethod by the PCF. Example embodiments provides an enhanced method forselecting a CHF by the PCF.

In an example, a UE may initiate a PDU session establishment procedure,during the procedure, a PCF may send a message to a CHF requestingcharging policy information. The CHF may send charging policyinformation to the PCF, the PCF may make policy decision based on thereceived charging policy information. FIG. 12 shows an example call flowwhich may comprise one or more actions.

A UE may send to an AMF a NAS message comprising at least one of:S-NSSAI(s), DNN, PDU Session ID, Request type, or N1 SM container (PDUsession establishment request). The UE may initiate a UE requested PDUsession establishment procedure by the transmission of a NAS messagecomprising a PDU session establishment request message within the N1 SMcontainer. The PDU session establishment request message may comprise atleast one of: a PDU session ID, Requested PDU Session Type, or aRequested SSC mode, etc. In response to the message received from theUE, the AMF may select an SMF and send to the SMF a message (e.g.PDUSession_CreateSMContext Request) comprising at least one of: SUPI,DNN, S-NSSAI(s) and/or network slice instance identifier(s), PDU SessionID, AMF ID, Request Type, PCF identifier, Priority Access, N1 SMcontainer (PDU Session Establishment Request), User locationinformation, Access Type, PEI). As an example, the PCF identifier may bean identifier, or an IP address, or FQDN to identify the PCF. Inresponse to the message received from the AMF, the SMF may send to theAMF a response message (e.g. PDUSession_CreateSMContext Response)comprising at least one of: Cause, SM Context ID or N1 SM container (PDUSession Reject (Cause)).

If dynamic PCC is deployed and a PCF ID is provided by the AMF, the SMFmay performs PCF selection procedure by selecting a PCF (e.g. based onthe PCF identifier received). The SMF may perform an SM PolicyAssociation Establishment procedure to establish a PDU Session with theselected PCF and get the default PCC Rules for the PDU Session. The PDUsession may be identified by the PDU Session ID. The message sent to thePCF by the SMF may comprise at least one of: at least one UE identity(e.g. SUPI, PEI, and/or GPSI), at least one UE IP address (e.g. UE IPv4address and/or UE IPv6 network prefix), Default 5QI and default ARP,Type of PDU Session (e.g. IPv4, IPv6, IPv4v6, Ethernet, Unstructured);Access Type (e.g. 3GPP access); RAT Type (e.g. 3GPP-NR-FDD); a PLMNidentifier; an application identifier; an allocated application instanceidentifier; DNN, S-NSSAI(s) and/or network slice instance identifier(s),PDU Session ID, user location information, or information of the SMF forthe PDU session (e.g. SMF identifier, IP address or FQDN of the SMF).

In response to the message received from the SMF, the PCF may select aCHF based on the information received from the SMF, and/or the UEsubscription information received from a UDR, and/or local configurationand operator policies, and/or other information for the PDU session. Asan example, the PCF may select a CHF based on one or more combinationinformation received from the SMF. As an example, the PCF may select aCHF based on the PLMN identifier received from the SMF. As an example,the PCF may select a CHF based on the network slice information (e.g.S-NSSAI(s) and/or network slice instance identifier(s)). As an example,the PCF may select a CHF based on the user location information. As anexample, the PCF may select a CHF based on the information of the SMF.As an example, the PCF may select a CHF based on the Access Type and theRAT type received from the SMF.

In an example, the PCF may select a CHF by an NRF. FIG. 19 is an examplecall flow of selecting a CHF by an NRF, which may one or more of thefollowing actions:

The PCF may send to an NRF a message (e.g. a CHF Selection Requestmessage, or a Nnrf_NFDiscovery_Request message) comprising aninformation element indication a request to select a CHF. The messagesent from the PCF to the NRF may comprise PDU session relatedinformation. The PDU session related information may comprise at leastone of: at least one UE identity (e.g. SUPI, PEI, and/or GPSI), at leastone UE IP address (e.g. UE IPv4 address and/or UE IPv6 network prefix),Default 5QI and default ARP, Type of PDU Session (e.g. IPv4, IPv6,IPv4v6, Ethernet, Unstructured); Access Type (e.g. 3GPP access); RATType (e.g. 3GPP-NR-FDD); the PLMN identifier; an application identifier;the DNN, the S-NSSAI(s) and/or network slice instance identifier(s), thePDU Session ID, the user location information, the information of theSMF for the PDU session (e.g. SMF identifier, IP address and/or FQDN ofthe SMF), or the information of the PCF (e.g. PCF identifier, IP addressand/or FQDN of the PCF).

In response to the message received from the PCF, the NRF maydetermine/select at least one CHF based on the information received fromthe PCF, and/or the UE subscription information received from a UDR,and/or local configuration and operator policies, and/or otherinformation for the PDU session. As an example, the NRF may select a CHFbased on one or more combination information received from the PCF. Asan example, the NRF may select a CHF based on the UE IP address (e.g. UEIPv4 address and/or UE IPv6 network prefix). As an example, the NRF mayselect a CHF based on the Type of PDU Session (e.g. IPv4, IPv6, IPv4v6,Ethernet, Unstructured). As an example, the NRF may select a CHF basedon the PDU Session ID. As an example, the NRF may select a CHF based onthe Access Type and/or the RAT type. As an example, the NRF may select aCHF based on the application identifier. As an example, the NRF mayselect a CHF based on the information of the SMF for the PDU session(e.g. SMF identifier, IP address or FQDN of the SMF). As an example, theNRF may select a CHF based on the user location information. As anexample, the NRF may select a CHF based on the information of the PCF(e.g. PCF identifier, IP address and/or FQDN of the PCF). The NRF maysend to the PCF a message (e.g. a CHF Selection Response message, or aNnrf_NFDiscovery_Request Response message) comprising the information ofthe at least one selected CHF (e.g. CHF identifier, IP address and/orFQDN of the at least one selected CHF).

The PCF may send to the CHF a message (e.g. charging policy request)requesting one or more charging policy information. The message sent tothe CHF may comprise at least one of: the at least one UE identity (e.g.SUPI, PEI, and/or GPSI), the at least one UE IP address (e.g. UE IPv4address and/or UE IPv6 network prefix), the Default 5QI and default ARP,the Type of PDU Session (e.g. IPv4, IPv6, IPv4v6, Ethernet,Unstructured); the Access Type (e.g. 3GPP access); the RAT Type (e.g.3GPP-NR-FDD); the PLMN identifier; the application identifier; theallocated application instance identifier; the DNN, the S-NSSAI(s)and/or network slice instance identifier(s), the PDU Session ID, theuser location information, the information of the SMF for the PDUsession (e.g. SMF identifier, IP address or FQDN of the SMF), or the PCFidentifier.

In response to the message received from the PCF, the CHF maydetermine/generate/create/derive charging policy information based onthe information received from the PCF. The charging policy informationmay comprise at least one of: an information element indicating a firstcharging method/charging type, wherein the first chargingmethod/charging type may comprise at least one of: online charging,offline charging, or converged charging; an information elementindicating at least one first charging rate; or an information elementindicating at least one first identifier or address of a CHF. The firstcharging method/charging type and/or first charging rate may be appliedto at least one of: a PDU session identified by a PDU sessionidentifier; a service data flow identified by at least one service dataflow filter; an application identified by an application identifier; awireless device identified by at least one user identity (e.g. SUPI,PEI, and/or GPSI); a data network identified by a DNN; or a networkslice identified by a S-NSSAI and/or a network slice instanceidentifier.

As an example, the CHF may determine charging policy information basedon the UE identity, e.g. the CHF may determine an online charging and/ora charging rate and/or an IP address (e.g. IPv4 address and/or IPv6network prefix) of CHF for an SUPI. As an example, the CHF may determinecharging policy information based on the type of PDU session, e.g. theCHF may determine an offline charging and/or a flat charging rate and/oran IPv4 address of CHF for an IPv4 type PDU session. As an example, theCHF may determine charging policy information based on the Access Typeand/or the RAT Type, e.g. the CHF may determine an online chargingand/or a charging rate and/or an IP address (e.g. IPv4 address and/orIPv6 network prefix) of CHF for an 3GPP access and/or 3GPP-NR-FDD RATtype. As an example, the CHF may determine charging policy informationbased on the PLMN identifier, e.g. the CHF may determine an offlinecharging and/or a flat charging rate and/or an FQDN of CHF for an PLMNidentifier “12345”. As an example, the CHF may determine charging policyinformation based on the application identifier, e.g. the CHF maydetermine an online charging and/or a charging rate and/or an identifierof CHF for an application identifier “skype”. As an example, the CHF maydetermine charging policy information based on the DNN, e.g. the CHF maydetermine an offline charging and/or a flat charging rate and/or an IPv4address of CHF for an DNN “IMS”. As an example, the CHF may determinecharging policy information based on the DNN, e.g. the CHF may determinean offline charging and/or a flat charging rate and/or an IPv4 addressof CHF for an DNN “IMS”. As an example, the CHF may determine chargingpolicy information based on the network slice, e.g. the CHF maydetermine an online charging and/or a charging rate and/or an IPv6network prefix of CHF for an S-NSSAI and/or network slice instance(s).As an example, the CHF may determine charging policy information basedon the PDU session identifier, e.g. the CHF may determine an onlinecharging and/or a charging rate and/or an IPv4 address of CHF for an PDUsession identifier “PDU session 1”. As an example, the CHF may determinecharging policy information based on the user location information, e.g.the CHF may determine an offline charging and/or a charging rate and/oran IP address (e.g. IPv4 address and/or IPv6 network prefix) of CHF fora wireless device located within “registration area 1”.

The CHF may send a response message (e.g. charging policy response) tothe PCF comprising the determined charging policy information. Themessage sent to the PCF may comprise at least one of: the at least oneUE identity (e.g. SUPI, PEI, and/or GPSI), the at least one UE IPaddress (e.g. UE IPv4 address and/or UE IPv6 network prefix), theDefault 5QI and default ARP, the Type of PDU Session (e.g. IPv4, IPv6,IPv4v6, Ethernet, Unstructured); the Access Type (e.g. 3GPP access); theRAT Type (e.g. 3GPP-NR-FDD); the PLMN identifier; the applicationidentifier; the DNN, the S-NSSAI(s) and/or network slice instanceidentifier(s), or the PDU Session ID.

As an example, HTTP protocol may be used for the communication betweenthe CHF and the PCF. FIG. 13 shows example definitions of informationelement for the charging policy information comprising charging method,charging rate and address of CHF, wherein XML structure of simpleelements and/or groups may be used as HTTP message content. As anexample, the transaction (e.g. a charging policy request message and acharging policy response message) between PCF and CHF may establish acharging control session between the PCF and the CHF. The PCF and theCHF may establish a charging control session for a wireless device,and/or a PDU session, and/or a DNN, and/or a network slice.

In response to the message received from the CHF, the PCF may makepolicy decision based on the received charging policy information, andmay determine/generate/create/derive one or more PCC rules comprisingone or more charging control rules, the one or more PCC rules and/or theone or more charging control rules may apply to at least one PDU sessionidentified by a PDU session identifier, and/or at least one service dataflow identified by at least one service data flow filter, and/or atleast one application identified by an application identifier, and/or awireless device identified by a UE identity, and/or a data networkidentified by a DNN, and/or a network slice identified by an S-NSSAIand/or a network slice instance identifier.

Each of the PCC rule determined by the PCF may comprise at least one of:at least one charging control rule; at least one policy control rulecomprising at least one QoS control rule and/or at least one gatingcontrol rule; at least one usage monitoring control rule; at least oneapplication detection and control rule; at least one traffic steeringcontrol rule; or at least one service data flow detection information(e.g. service data flow template).

As an example, the charging control rule may be used for chargingcontrol and may comprise at least one of: an information elementindicating a second charging method/charging type, wherein the secondcharging method/charging type may comprise at least one of: onlinecharging, offline charging, or converged charging; an informationelement indicating at least one second charging rate; or an informationelement indicating at least one second identifier or address of a CHF.

As an example, the policy control rule may be used for policy control,wherein the at least one QoS control rule may be used for QoS controland the at least one gating control rule may be used for gating control.As an example, the QoS control rule may be used to authorize QoS on aservice data flow. As an example, the gating control rule may be used todiscard packets that don't match any service data flow of the gatingcontrol rule and/or associated PCC rules. As an example, the usagemonitoring control rule may be used to monitor, both volume and timeusage, and report the accumulated usage of network resources. As anexample, the application detection and control rule may comprise arequest to detect a specified application traffic, report to a PCF on astart or stop of application traffic and to apply a specifiedenforcement and charging actions. As an example, the traffic steeringcontrol rule may be used to activate/deactivate traffic steeringpolicies for steering a subscriber's traffic to appropriate operator or3rd party service functions (e.g. NAT, antimalware, parental control,DDoS protection) in an (S)Gi-LAN.

As an example, the service data flow detection information (e.g. servicedata flow template) may comprise a list of service data flow filters oran application identifier that references the corresponding applicationdetection filter for the detection of the service data flow. As anexample, the service data flow detection information (e.g. service dataflow template) may comprise combination of traffic patterns of theEthernet PDU traffic.

As an example, the PCF may determine charging control rules based oncharging policy information and/or other information (e.g. localconfiguration and operator policies, or subscription information). As anexample, the PCF may determine the second charging method/charging typein the charging control rule based on the first charging method/chargingtype in the charging policy information. The second chargingmethod/charging type may be the same as the first chargingmethod/charging type or may be different. As an example, the PCF maydetermine an online charging method in the charging control rule basedon the online charging method in the charging policy information. As anexample, the PCF may determine a converged charging method in thecharging control rule based on the converged charging method in thecharging policy information. As an example, the PCF may determine anoffline charging method in the charging control rule based on aconverged charging method in the charging policy information. As anexample, the PCF may determine an online charging method in the chargingcontrol rule based on an offline charging method in the charging policyinformation and the online charging method in a local configuration andoperator policies.

As an example, the PCF may determine the second charging rate in thecharging control rule based on the first charging rate in the chargingpolicy information. The second charging rate may be the same as thefirst charging rate or may be different. As an example, the PCF maydetermine a charging rate 1 in the charging control rule based on thecharging rate 1 in the charging policy information. As an example, thePCF may determine a charging rate 1 in the charging control rule basedon a charging rate 2 in the charging policy information and a chargingrate 1 in the subscription information (e.g. from a UDR).

As an example, the PCF may determine the second identifier or address ofa CHF in the charging control rule based on the first identifier oraddress of a CHF in the charging policy information. The secondidentifier or address of the CHF may be the same as the first identifieror address of a CHF or may be different. As an example, the PCF maydetermine an IPv4 address of a CHF in the charging control rule based onthe IPv4 address of the CHF in the charging policy information. As anexample, the PCF may determine an IPv6 network prefix address of a CHFin the charging control rule based on the an IPv4 address and the IPv6network prefix address of the CHF in the charging policy information. Asan example, the PCF may determine an identifier of a CHF in the chargingcontrol rule based on an FQDN of the CHF in the charging policyinformation.

As an example, the PCF may connect with one or more CHFs. The PCF mayrequest to the one or more CHFs and receive charging policy informationfrom the one or more CHFs respectively. The PCF may determine eachcharging control rule based on each charging policy informationrespectively. As an example, the PCF may determine charging control rule1 based on charging policy information 1 received from CHF 1, anddetermine charging control rule 2 based on charging policy information 2received from CHF 2. As an example, the PCF may determine chargingcontrol rule 3 and charging control rule 4 based on charging policyinformation 3 received from CHF 3, and determine charging control rule 5and charging control rule 6 based on charging policy information 4received from CHF 4.

The PCF may send to the SMF a response message (e.g. SM PolicyAssociation Establishment Response) comprising one or more PCC rulescomprising one or more charging control rules. As an example, theresponse message may comprise one or more PCC rules associate with oneCHF (e.g. one or more PCC rules comprising one or more charging controlrules may be derived from charging policy information received from CHF1). As an example, the response message may comprise one or more PCCrules associate with more than one CHFs (e.g. PCC rule 1 comprises oneor more charging control rules 1, and PCC rule 2 comprises one or morecharging control rules 2, where PCC rule 1 and/or charging control rules1 may be derived from charging policy information received from CHF 1,and PCC rule 2 and/or charging control rules 2 may be derived fromcharging policy information received from CHF 2. As an example, chargingcontrol rules 1 may comprise the address of CHF 1, charging controlrules 2 may comprise the address of CHF 2). The response message maycomprise at least one of the following information elements which theone or more PCC rules applied to: the at least one UE identity (e.g.SUPI, PEI, and/or GPSI), the at least one UE IP address (e.g. UE IPv4address and/or UE IPv6 network prefix), the Default 5QI and default ARP,the Type of PDU Session (e.g. IPv4, IPv6, IPv4v6, Ethernet,Unstructured); the Access Type (e.g. 3GPP access); the RAT Type (e.g.3GPP-NR-FDD); the PLMN identifier; the application identifier; the DNN,the S-NSSAI(s) and/or network slice instance identifier(s), or the PDUSession ID.

In response to the message received from the PCF, the SMF may installthe one or more PCC rules and other information received. The SMF mayselect one of CHF and enforce charging control rules associated with theCHF by comprising one or more actions. Based on the charging controlrules and other information elements, the SMF may construct a message(e.g. charging data request [initial]) and send the constructed messageto the CHF to establish a charging session. The identifier or address ofthe CHF in the charging control rule may be used by the SMF to establisha charging session. The message sent to the CHF may comprise at leastone of the following: an information element indicating a requestedcharging method/charging type, wherein the charging method/charging typemay comprise at least one of: online charging, offline charging, orconverged charging; an information element indicating at least onerequested charging rate; an information element indicating a PDU sessionidentified by a PDU session identifier; an information elementindicating at least one service data flow identified by at least oneservice data flow filter; an information element indicating anapplication identified by an application identifier; an informationelement indicating a wireless device identified by at least one useridentity (e.g. SUPI, PEI, and/or GPSI); an information elementindicating a data network identified by a DNN; or an information elementindicating a network slice identified by a S-NSSAI and/or a networkslice instance identifier.

As an example, the SMF may indicate to the CHF an online chargingmethod; as an example, the SMF may indicated to the CHF an offlinecharging method; as an example, the SMF may indicate to the CHF aconverged charging method. In response to the message received from theSMF, the CHF may verify the information received and determine whetherto accept the charging session establishment request. As an example, theCHF may accept the request, and may send to the SMF a response message(e.g. charging data response). The response message may comprise atleast one of the following: an information element indicating a successcause value to indicate the request is accepted; an information elementindicating an accepted charging method/charging type, wherein theaccepted charging method/charging type may comprise at least one of:online charging, offline charging, or converged charging; as an example,the accepted charging method/charging type may be the same as therequested charging method/charging type; an information elementindicating at least one charging rate (e.g. rating group); aninformation element indicating at least one granted unit (e.g. grantedvolume and/or granted time for online charging or converged charging);an information element indicating final unit action (e.g. redirect thetraffic to a web portal when the final granted unit has been consumed bythe wireless device); an information element indicating a PDU sessionidentified by a PDU session identifier; an information elementindicating at least one service data flow identified by at least oneservice data flow filter; an information element indicating anapplication identified by an application identifier; an informationelement indicating a wireless device identified by at least one useridentity (e.g. SUPI, PEI, and/or GPSI); an information elementindicating a data network identified by a DNN; or an information elementindicating a network slice identified by a S-NSSAI and/or a networkslice instance identifier.

As an example, the CHF may reject the request, and may send to the SMF aresponse message (e.g. charging data response) comprising a proposedcharging method/charging type. The response message may comprise atleast one of the following: an information element indicating a rejectcause value to indicate the request is rejected; or an informationelement indicating an accepted charging method/charging type, whereinthe accepted charging method/charging type proposed by the CHF maycomprise at least one of: online charging, offline charging, orconverged charging; as an example, the accepted charging method/chargingtype may be different from the requested charging method/charging type.As an example, the requested charging method may be offline charging,and the proposed accepted charging method may be converged charging.

In response to the message received from the CHF, the SMF may takedifferent actions based on the result of the response. As an example,when receiving a reject response message from the CHF, the SMF mayresend to the CHF a second request message (e.g. charging data request)comprising the accepted charging method/charging type proposed by theCHF. As an example, the requested charging method in the second requestmessage may be set as the proposed accepted charging method in theresponse message (e.g. converged charging). The CHF may accept thesecond request by sending to the CHF a second response message (e.g.charging data response) comprising a success cause value indicating therequest is accepted. As an example, when receiving a reject responsemessage from the CHF, the SMF may select a second CHF from theinformation (e.g. charging policy rules) received from the PCF and senda request message (e.g. charging data request) to the second CHF toestablish a charging session.

As an example, after receiving a success response message from the CHF,the SMF may enforce the PCC rules and/or charging control rules requiredby the PCF and/or charging function required by the CHF bydetermining/generating/creating/deriving at least one of the followinguser plane rules based on the received PCC rules and/or charging controlrules from the PCF and/or the information (e.g. charging policyinformation) received from the CHF: at least one packet detection rule;at least one forwarding action rule; at least one QoS enforcement rule;or at least one usage reporting rule.

As an example, the packet detection rule may comprise data/trafficpacket detection information, e.g. one or more match fields againstwhich incoming packets are matched and may apply other user plane rules(e.g. forwarding action rule, QoS enforcement rule, and usage reportingrule) to the data/traffic packets matching the packet detection rule. Asan example, the forwarding action rule may comprise an apply actionparameter, which may indicate whether a UP function may forward,duplicate, drop or buffer the data/traffic packet respectively. As anexample, the usage reporting rule may be used to measure the networkresources usage in terms of traffic data volume, duration (i.e. time)and/or events, according to a measurement method in the usage reportingrule. As an example, the QoS enforcement rule contains instructions torequest the UP function to perform QoS enforcement of the user planetraffic. As an example, the SMF may determine a packet detection rulebased on the service data flow detection information (e.g. service dataflow template) received from the PCF. As an example, the SMF maydetermine a forwarding action rule based on the policy control ruleand/or usage monitoring control rule received from the PCF and/or thefinal unit action received from the CHF. As an example, the SMF maydetermine a QoS enforcement rule based on the policy control rule (e.g.QoS control rule) received from the PCF. As an example, the SMF maydetermine a usage reporting rule based on the usage monitoring controlrule received from the PCF and/or the at least one granted unit (e.g.granted volume and/or granted time for online charging or convergedcharging) received from the CHF.

As an example, the SMF may enforce the PCC rules and/or charging controlrules required by the PCF and/or charging function required by the CHFby selecting a UPF and sending to the UPF a message (e.g. N4 sessionestablishment/modification request) comprising the at least one of thefollowing user plane rules: at least one packet detection rule; at leastone forwarding action rule; at least one QoS enforcement rule; or atleast one usage reporting rule.

In response to the message received from the SMF, the UPF may installthe user plane rules, send to the SMF a response message (e.g. N4session establishment/modification response), and enforce the user planerules received from the SMF. As an example, the UPF may enforce the atleast one packet detection rule by matching a user data/traffic packetwith service data flow template (e.g. service data flow filters and/orapplication identifiers), and may apply other user plane rules (e.g.forwarding action rule, QoS enforcement rule, and usage reporting rule)to the data/traffic packets matched the packet detection rule. As anexample, the UPF may enforce the at least one forwarding action rule byforwarding, duplicating, dropping or buffering a data/traffic packetrespectively. As an example, the UPF may redirect the traffic to a webportal of the operator. As an example, the UPF may enforce the at leastone usage reporting rule by measuring network resources usage in termsof traffic data volume, duration (i.e. time) and/or events, according toa measurement method in the usage reporting rule; the UPF may report thenetwork resources usage to the SMF when the quota/threshold reached,and/or event and/or another trigger is (are) met. As an example, the UPFmay enforce the at least one QoS enforcement rule by applying at leastone of QoS parameters: 5QI, ARP, MBR, GBR to a service data flow; as anexample, the UPF may enforce the at least one QoS enforcement rule byapplying at least one of QoS parameters: Session AMBR and default5QI/ARP combination to a PDU session.

As an example, the SMF and/or UPF may enforce the charging control rulesby performing at least one of the following actions: receiving, by theSMF, a charging control rule from a PCF; determining, by the SMF, atleast one of the user plane rules: at least one packet detection rule;at least one forwarding action rule; at least one QoS enforcement rule;or at least one usage reporting rule, sending, by the SMF to the UPF theat least one of the user plane rules; enforcing, by the UPF, the atleast one of the user plane rules; reporting, by the UPF, usage reportinformation to the SMF; or sending, by the SMF, the usage reportinformation to the CHF.

As an example, the usage report information may comprise networkresources usage in terms of traffic data volume, duration (i.e. time)applied to at least one of: a wireless device, a PDU session, a servicedata flow, an application, a network slice, or a data network.

The SMF may interact with the AMF, in an example, the SMF may send tothe AMF a Namf_Communication_N1N2MessageTransfer message comprising oneor more of: PDU Session ID, QoS Profile(s), CN Tunnel Info, and S-NSSAIfrom the Allowed NSSAI.

In an example, the AMF may interact with (R)AN and UE by sending to the(R)AN a N2 PDU Session Request message comprising the informationreceived from the SMF, indicating the PDU session establishment isaccepted.

In an example, the (R)AN may send to the AMF a N2 PDU Session Responsemessage comprising one or more of: PDU Session ID, N2 SM information(PDU Session ID, AN Tunnel Info, List of accepted/rejected QFI(s)),wherein the AN Tunnel Info may be corresponding to the Access Networkaddress of the N3 tunnel corresponding to the PDU Session.

In an example, the AMF may send to the SMF aNsmf_PDUSession_UpdateSMContext Request message comprising the N2 SMinformation received from (R)AN to the SMF.

In an example, the SMF may initiate an N4 Session Modification procedurewith the UPF. The SMF may provide AN Tunnel Info to the UPF as well asthe corresponding forwarding rules. The UPF may send to the SMF aresponse message.

In an example, the SMF may request quota from CHF, e.g. “start ofservice data flow” event may need quota from CHF. The SMF may send amessage to the CHF (e.g. Charging Data Request [update]). As an example,for online charging or converged charging, the SMF may request quotafrom CHF when allocated quota is consumed or a trigger is met to requesta quota.

As an example, the UPF may report resource usage of a PDU session to theSMF. As an example, the UPF may report resource usage of a wirelessdevice to the SMF, by enforcing the charging control rules, the SMF maysend to the CHF a message (e.g. Charging Data Request [update])comprising resource usage information received from the UPF. In anexample, the CHF may update CDR for this PDU session. The CHF mayacknowledge the SMF by sending a Charging Data Response message. In anexample, the SMF may send to the AMF a Nsmf_PDUSession_UpdateSMContextResponse message. In an example, other interactions may be performedbetween SMF, AMF, (R)AN and UE for the PDU session establishmentprocedure. FIG. 14 , FIG. 15 and FIG. 16 are example diagram depictingthe procedures of PCF, CHF and SMF respectively as per an aspect of anembodiment of the present disclosure.

In an example, a UE may initiate a PDU session establishment procedure,during the procedure, a PCF may send a message to a network function(NF) requesting charging policy information. The NF may request chargingpolicy information from a CHF and send the charging policy informationto the PCF, the PCF may make policy decision based on the receivedcharging policy information. FIG. 17 shows an example call flow whichmay comprise one or more of the following actions:

A UE may send to an AMF a NAS message comprising at least one of:S-NSSAI(s), DNN, PDU Session ID, Request type, or N1 SM container (PDUsession establishment request). The UE may initiate a UE requested PDUsession establishment procedure by the transmission of a NAS messagecomprising a PDU session establishment request message within the N1 SMcontainer. The PDU session establishment request message may comprise atleast one of: a PDU session ID, Requested PDU Session Type, or aRequested SSC mode, etc.

In response to the message received from the UE, the AMF may select anSMF and send to the SMF a message (e.g. PDUSession_CreateSMContextRequest) comprising at least one of: SUPI, DNN, S-NSSAI(s) and/ornetwork slice instance identifier(s), PDU Session ID, AMF ID, RequestType, PCF identifier, Priority Access, N1 SM container (PDU SessionEstablishment Request), User location information, Access Type, PEI). Asan example, the PCF identifier may be an identifier, or an IP address,or FQDN to identify the PCF. In response to the message received fromthe AMF, the SMF may send to the AMF a response message (e.g.PDUSession_CreateSMContext Response) comprising at least one of: Cause,SM Context ID or N1 SM container (PDU Session Reject (Cause)).

If dynamic PCC is deployed and a PCF ID is provided by the AMF, the SMFmay performs PCF selection procedure by selecting a PCF (e.g. based onthe PCF identifier received). The SMF may perform an SM PolicyAssociation Establishment procedure to establish a PDU Session with theselected PCF and get the default PCC Rules for the PDU Session. The PDUsession may be identified by the PDU Session ID. The message sent to thePCF by the SMF may comprise at least one of: at least one UE identity(e.g. SUPI, PEI, and/or GPSI), at least one UE IP address (e.g. UE IPv4address and/or UE IPv6 network prefix), Default 5QI and default ARP,Type of PDU Session (e.g. IPv4, IPv6, IPv4v6, Ethernet, Unstructured);Access Type (e.g. 3GPP access); RAT Type (e.g. 3GPP-NR-FDD); a PLMNidentifier; an application identifier; an allocated application instanceidentifier; DNN, S-NSSAI(s) and/or network slice instance identifier(s),PDU Session ID, user location information, or information of the SMF forthe PDU session (e.g. SMF identifier, IP address or FQDN of the SMF).

In response to the message received from the SMF, the PCF may send amessage (e.g. charging policy request) to an NF, and the message maycomprise at least one of: at least one UE identity (e.g. SUPI, PEI,and/or GPSI), at least one UE IP address (e.g. UE IPv4 address and/or UEIPv6 network prefix), Default 5QI and default ARP, Type of PDU Session(e.g. IPv4, IPv6, IPv4v6, Ethernet, Unstructured); Access Type (e.g.3GPP access); RAT Type (e.g. 3GPP-NR-FDD); a PLMN identifier; anapplication identifier; an allocated application instance identifier;DNN, S-NSSAI(s) and/or network slice instance identifier(s), PDU SessionID, user location information, or information of the SMF for the PDUsession (e.g. SMF identifier, IP address or FQDN of the SMF).

As an example, the NF may be a network exposure function (NEF). As anexample, the NF may be an operation administration and maintenance(OAM). As an example, the NF may be a charging function agent whichconnects to one or more CHFs. In response to the message received fromthe PCF, the NF (e.g. an NEF) may select a CHF based on the informationreceived from the PCF, and/or the UE subscription information receivedfrom a UDR, and/or local configuration and operator policies, and/orother information for the PDU session. As an example, the NF may selecta CHF based on one or more combination information received from thePCF. As an example, the NF may select a CHF based on the PLMNidentifier. As an example, the NF may select a CHF based on the networkslice information (e.g. S-NSSAI(s) and/or network slice instanceidentifier(s)). As an example, the NF may select a CHF based on the userlocation information. As an example, the NF may select a CHF based onthe information of the SMF. As an example, the NF may select a CHF basedon the Access Type and the RAT type.

The NF may send to the CHF a message (e.g. charging policy request)requesting one or more charging policy information. The message sent tothe CHF may comprise at least one of: the at least one UE identity (e.g.SUPI, PEI, and/or GPSI), the at least one UE IP address (e.g. UE IPv4address and/or UE IPv6 network prefix), the Default 5QI and default ARP,the Type of PDU Session (e.g. IPv4, IPv6, IPv4v6, Ethernet,Unstructured); the Access Type (e.g. 3GPP access); the RAT Type (e.g.3GPP-NR-FDD); the PLMN identifier; the application identifier; theallocated application instance identifier; the DNN, the S-NSSAI(s)and/or network slice instance identifier(s), the PDU Session ID, theuser location information, the information of the SMF for the PDUsession (e.g. SMF identifier, IP address or FQDN of the SMF), or the PCFidentifier.

In response to the message received from the NF, the CHF maydetermine/generate/create/derive charging policy information based onthe information received from the NF. The charging policy informationmay comprise at least one of: an information element indicating a firstcharging method/charging type, wherein the first chargingmethod/charging type may comprise at least one of: online charging,offline charging, or converged charging; an information elementindicating at least one first charging rate; an information elementindicating at least one first identifier or address of a CHF. The firstcharging method/charging type and/or first charging rate may be appliedto at least one of: a PDU session identified by a PDU sessionidentifier; a service data flow identified by at least one service dataflow filter; an application identified by an application identifier; awireless device identified by at least one user identity (e.g. SUPI,PEI, and/or GPSI); a data network identified by a DNN; or a networkslice identified by a S-NSSAI and/or a network slice instanceidentifier.

As an example, the CHF may determine charging policy information basedon the UE identity, e.g. the CHF may determine an online charging and/ora charging rate and/or an IP address (e.g. IPv4 address and/or IPv6network prefix) of CHF for an SUPI. As an example, the CHF may determinecharging policy information based on the type of PDU session, e.g. theCHF may determine an offline charging and/or a flat charging rate and/oran IPv4 address of CHF for an IPv4 type PDU session. As an example, theCHF may determine charging policy information based on the Access Typeand/or the RAT Type, e.g. the CHF may determine an online chargingand/or a charging rate and/or an IP address (e.g. IPv4 address and/orIPv6 network prefix) of CHF for an 3GPP access and/or 3GPP-NR-FDD RATtype. As an example, the CHF may determine charging policy informationbased on the PLMN identifier, e.g. the CHF may determine an offlinecharging and/or a flat charging rate and/or an FQDN of CHF for an PLMNidentifier “12345”. As an example, the CHF may determine charging policyinformation based on the application identifier, e.g. the CHF maydetermine an online charging and/or a charging rate and/or an identifierof CHF for an application identifier “skype”. As an example, the CHF maydetermine charging policy information based on the DNN, e.g. the CHF maydetermine an offline charging and/or a flat charging rate and/or an IPv4address of CHF for an DNN “IMS”. As an example, the CHF may determinecharging policy information based on the DNN, e.g. the CHF may determinean offline charging and/or a flat charging rate and/or an IPv4 addressof CHF for an DNN “IMS”. As an example, the CHF may determine chargingpolicy information based on the network slice, e.g. the CHF maydetermine an online charging and/or a charging rate and/or an IPv6network prefix of CHF for an S-NSSAI and/or network slice instance(s).As an example, the CHF may determine charging policy information basedon the PDU session identifier, e.g. the CHF may determine an onlinecharging and/or a charging rate and/or an IPv4 address of CHF for an PDUsession identifier “PDU session 1”. As an example, the CHF may determinecharging policy information based on the user location information, e.g.the CHF may determine an offline charging and/or a charging rate and/oran IP address (e.g. IPv4 address and/or IPv6 network prefix) of CHF fora wireless device located within “registration area 1”.

The CHF may send a response message (e.g. charging policy response) tothe NF comprising the determined charging policy information. Themessage sent to the NF may comprise at least one of: the at least one UEidentity (e.g. SUPI, PEI, and/or GPSI), the at least one UE IP address(e.g. UE IPv4 address and/or UE IPv6 network prefix), the Default 5QIand default ARP, the Type of PDU Session (e.g. IPv4, IPv6, IPv4v6,Ethernet, Unstructured); the Access Type (e.g. 3GPP access); the RATType (e.g. 3GPP-NR-FDD); the PLMN identifier; the applicationidentifier; the DNN, the S-NSSAI(s) and/or network slice instanceidentifier(s), or the PDU Session ID.

In response to the message received from the CHF, the NF may send to thePCF a response message (e.g. charging policy response) comprising thecharging policy information received from the CHF. The message sent tothe PCF may comprise at least one of: the at least one UE identity (e.g.SUPI, PEI, and/or GPSI), the at least one UE IP address (e.g. UE IPv4address and/or UE IPv6 network prefix), the Default 5QI and default ARP,the Type of PDU Session (e.g. IPv4, IPv6, IPv4v6, Ethernet,Unstructured); the Access Type (e.g. 3GPP access); the RAT Type (e.g.3GPP-NR-FDD); the PLMN identifier; the application identifier; the DNN,the S-NSSAI(s) and/or network slice instance identifier(s), or the PDUSession ID.

In response to the message received from the NF, the PCF may make policydecision based on the received charging policy information, and maydetermine/generate/create/derive one or more PCC rules comprising one ormore charging control rules, the one or more PCC rules and/or the one ormore charging control rules may apply to at least one PDU sessionidentified by a PDU session identifier, and/or at least one service dataflow identified by at least one service data flow filter, and/or atleast one application identified by an application identifier, and/or awireless device identified by a UE identity, and/or a data networkidentified by a DNN, and/or a network slice identified by an S-NSSAIand/or a network slice instance identifier.

Each of the PCC rule determined by the PCF may comprise at least one of:at least one charging control rule; at least one policy control rulecomprising at least one QoS control rule and/or at least one gatingcontrol rule; at least one usage monitoring control rule; at least oneapplication detection and control rule; at least one traffic steeringcontrol rule; or at least one service data flow detection information(e.g. service data flow template). As an example, the charging controlrule may be used for charging control and may comprise at least one of:an information element indicating a second charging method/chargingtype, wherein the second charging method/charging type may comprise atleast one of: online charging, offline charging, or converged charging;an information element indicating at least one second charging rate; oran information element indicating at least one second identifier oraddress of a CHF.

As an example, the policy control rule may be used for policy control,wherein the at least one QoS control rule may be used for QoS controland the at least one gating control rule may be used for gating control.As an example, the QoS control rule may be used to authorize QoS on aservice data flow. As an example, the gating control rule may be used todiscard packets that don't match any service data flow of the gatingcontrol rule and/or associated PCC rules.

As an example, the usage monitoring control rule may be used to monitor,both volume and time usage, and report the accumulated usage of networkresources. As an example, the application detection and control rule maycomprise a request to detect a specified application traffic, report toa PCF on a start or stop of application traffic and to apply a specifiedenforcement and charging actions. As an example, the traffic steeringcontrol rule may be used to activate/deactivate traffic steeringpolicies for steering a subscriber's traffic to appropriate operator or3rd party service functions (e.g. NAT, antimalware, parental control,DDoS protection) in an (S)Gi-LAN. As an example, the service data flowdetection information (e.g. service data flow template) may comprise alist of service data flow filters or an application identifier thatreferences the corresponding application detection filter for thedetection of the service data flow. As an example, the service data flowdetection information (e.g. service data flow template) may comprisecombination of traffic patterns of the Ethernet PDU traffic.

As an example, the PCF may determine charging control rules based oncharging policy information and/or other information (e.g. localconfiguration and operator policies, or subscription information). As anexample, the PCF may determine the second charging method/charging typein the charging control rule based on the first charging method/chargingtype in the charging policy information. The second chargingmethod/charging type may be the same as the first chargingmethod/charging type or may be different. As an example, the PCF maydetermine an online charging method in the charging control rule basedon the online charging method in the charging policy information. As anexample, the PCF may determine a converged charging method in thecharging control rule based on the converged charging method in thecharging policy information. As an example, the PCF may determine anoffline charging method in the charging control rule based on aconverged charging method in the charging policy information. As anexample, the PCF may determine an online charging method in the chargingcontrol rule based on an offline charging method in the charging policyinformation and the online charging method in a local configuration andoperator policies.

As an example, the PCF may determine the second charging rate in thecharging control rule based on the first charging rate in the chargingpolicy information. The second charging rate may be the same as thefirst charging rate or may be different. As an example, the PCF maydetermine a charging rate 1 in the charging control rule based on thecharging rate 1 in the charging policy information. As an example, thePCF may determine a charging rate 1 in the charging control rule basedon a charging rate 2 in the charging policy information and a chargingrate 1 in the subscription information (e.g. from a UDR).

As an example, the PCF may determine the second identifier or address ofa CHF in the charging control rule based on the first identifier oraddress of a CHF in the charging policy information. The secondidentifier or address of the CHF may be the same as the first identifieror address of a CHF or may be different. As an example, the PCF maydetermine an IPv4 address of a CHF in the charging control rule based onthe IPv4 address of the CHF in the charging policy information. As anexample, the PCF may determine an IPv6 network prefix address of a CHFin the charging control rule based on the an IPv4 address and the IPv6network prefix address of the CHF in the charging policy information. Asan example, the PCF may determine an identifier of a CHF in the chargingcontrol rule based on an FQDN of the CHF in the charging policyinformation.

As an example, the PCF may connect with one or more CHFs. The PCF mayrequest to the one or more CHFs and receive charging policy informationfrom the one or more CHFs respectively. The PCF may determine eachcharging control rule based on each charging policy informationrespectively. As an example, the PCF may determine charging control rule1 based on charging policy information 1 received from CHF 1, anddetermine charging control rule 2 based on charging policy information 2received from CHF 2. As an example, the PCF may determine chargingcontrol rule 3 and charging control rule 4 based on charging policyinformation 3 received from CHF 3, and determine charging control rule 5and charging control rule 6 based on charging policy information 4received from CHF 4.

The PCF may send to the SMF a response message (e.g. SM PolicyAssociation Establishment Response) comprising one or more PCC rulescomprising one or more charging control rules. As an example, theresponse message may comprise one or more PCC rules associate with oneCHF (e.g. one or more PCC rules comprising one or more charging controlrules may be derived from charging policy information received from CHF1). As an example, the response message may comprise one or more PCCrules associate with more than one CHFs (e.g. PCC rule 1 comprises oneor more charging control rules 1, and PCC rule 2 comprises one or morecharging control rules 2, where PCC rule 1 and/or charging control rules1 may be derived from charging policy information received from CHF 1,and PCC rule 2 and/or charging control rules 2 may be derived fromcharging policy information received from CHF 2. As an example, chargingcontrol rules 1 may comprise the address of CHF 1, charging controlrules 2 may comprise the address of CHF 2). The response message maycomprise at least one of the following information elements which theone or more PCC rules applied to: the at least one UE identity (e.g.SUPI, PEI, and/or GPSI), the at least one UE IP address (e.g. UE IPv4address and/or UE IPv6 network prefix), the Default 5QI and default ARP,the Type of PDU Session (e.g. IPv4, IPv6, IPv4v6, Ethernet,Unstructured); the Access Type (e.g. 3GPP access); the RAT Type (e.g.3GPP-NR-FDD); the PLMN identifier; the application identifier; the DNN,the S-NSSAI(s) and/or network slice instance identifier(s), or the PDUSession ID.

In response to the message received from the PCF, the SMF may installthe one or more PCC rules and other information received. The SMF mayselect one of CHF and enforce charging control rules associated with theCHF by comprising at least one of the following actions: based on thecharging control rules and other information elements, the SMF mayconstruct a message (e.g. charging data request [initial]) and send theconstructed message to the CHF to establish a charging session. Theidentifier or address of the CHF in the charging control rule may beused by the SMF to establish a charging session. The message sent to theCHF may comprise at least one of the following: an information elementindicating a requested charging method/charging type, wherein thecharging method/charging type may comprise at least one of: onlinecharging, offline charging, or converged charging; an informationelement indicating at least one requested charging rate; an informationelement indicating a PDU session identified by a PDU session identifier;an information element indicating at least one service data flowidentified by at least one service data flow filter; an informationelement indicating an application identified by an applicationidentifier; an information element indicating a wireless deviceidentified by at least one user identity (e.g. SUPI, PEI, and/or GPSI);an information element indicating a data network identified by a DNN; oran information element indicating a network slice identified by aS-NSSAI and/or a network slice instance identifier.

As an example, the SMF may indicate to the CHF an online chargingmethod; as an example, the SMF may indicated to the CHF an offlinecharging method; as an example, the SMF may indicate to the CHF aconverged charging method. In response to the message received from theSMF, the CHF may verify the information received and determine whetherto accept the charging session establishment request. As an example, theCHF may accept the request, and may send to the SMF a response message(e.g. charging data response). The response message may comprise atleast one of the following: an information element indicating a successcause value to indicate the request is accepted; an information elementindicating an accepted charging method/charging type, wherein theaccepted charging method/charging type may comprise at least one of:online charging, offline charging, or converged charging; as an example,the accepted charging method/charging type may be the same as therequested charging method/charging type; an information elementindicating at least one charging rate (e.g. rating group); aninformation element indicating at least one granted unit (e.g. grantedvolume and/or granted time for online charging or converged charging);an information element indicating final unit action (e.g. redirect thetraffic to a web portal when the final granted unit has been consumed bythe wireless device); an information element indicating a PDU sessionidentified by a PDU session identifier; an information elementindicating at least one service data flow identified by at least oneservice data flow filter; an information element indicating anapplication identified by an application identifier; an informationelement indicating a wireless device identified by at least one useridentity (e.g. SUPI, PEI, and/or GPSI); an information elementindicating a data network identified by a DNN; or an information elementindicating a network slice identified by a S-NSSAI and/or a networkslice instance identifier.

As an example, the CHF may reject the request, and may send to the SMF aresponse message (e.g. charging data response) comprising a proposedcharging method/charging type. The response message may comprise atleast one of the following: an information element indicating a rejectcause value to indicate the request is rejected; or an informationelement indicating an accepted charging method/charging type, whereinthe accepted charging method/charging type proposed by the CHF maycomprise at least one of: online charging, offline charging, orconverged charging; as an example, the accepted charging method/chargingtype may be different from the requested charging method/charging type.As an example, the requested charging method may be offline charging,and the proposed accepted charging method may be converged charging.

In response to the message received from the CHF, the SMF may takedifferent actions based on the result of the response. As an example,when receiving a reject response message from the CHF, the SMF mayresend to the CHF a second request message (e.g. charging data request)comprising the accepted charging method/charging type proposed by theCHF. As an example, the requested charging method in the second requestmessage may be set as the proposed accepted charging method in theresponse message (e.g. converged charging). The CHF may accept thesecond request by sending to the CHF a second response message (e.g.charging data response) comprising a success cause value indicating therequest is accepted. As an example, when receiving a reject responsemessage from the CHF, the SMF may select a second CHF from theinformation (e.g. charging policy rules) received from the PCF and senda request message (e.g. charging data request) to the second CHF toestablish a charging session. As an example, after receiving a successresponse message from the CHF, the SMF may enforce the PCC rules and/orcharging control rules required by the PCF and/or charging functionrequired by the CHF by determining/generating/creating/deriving at leastone of the following user plane rules based on the received PCC rulesand/or charging control rules from the PCF and/or the information (e.g.charging policy information) received from the CHF: at least one packetdetection rule; at least one forwarding action rule; at least one QoSenforcement rule; or at least one usage reporting rule.

As an example, the packet detection rule may comprise data/trafficpacket detection information, e.g. one or more match fields againstwhich incoming packets are matched and may apply other user plane rules(e.g. forwarding action rule, QoS enforcement rule, and usage reportingrule) to the data/traffic packets matching the packet detection rule. Asan example, the forwarding action rule may comprise an apply actionparameter, which may indicate whether a UP function may forward,duplicate, drop or buffer the data/traffic packet respectively. As anexample, the usage reporting rule may be used to measure the networkresources usage in terms of traffic data volume, duration (i.e. time)and/or events, according to a measurement method in the usage reportingrule. As an example, the QoS enforcement rule contains instructions torequest the UP function to perform QoS enforcement of the user planetraffic. As an example, the SMF may determine a packet detection rulebased on the service data flow detection information (e.g. service dataflow template) received from the PCF. As an example, the SMF maydetermine a forwarding action rule based on the policy control ruleand/or usage monitoring control rule received from the PCF and/or thefinal unit action received from the CHF. As an example, the SMF maydetermine a QoS enforcement rule based on the policy control rule (e.g.QoS control rule) received from the PCF. As an example, the SMF maydetermine a usage reporting rule based on the usage monitoring controlrule received from the PCF and/or the at least one granted unit (e.g.granted volume and/or granted time for online charging or convergedcharging) received from the CHF.

As an example, the SMF may enforce the PCC rules and/or charging controlrules required by the PCF and/or charging function required by the CHFby selecting a UPF and sending to the UPF a message (e.g. N4 sessionestablishment/modification request) comprising the at least one of thefollowing user plane rules: at least one packet detection rule; at leastone forwarding action rule; at least one QoS enforcement rule; or atleast one usage reporting rule. In response to the message received fromthe SMF, the UPF may install the user plane rules, send to the SMF aresponse message (e.g. N4 session establishment/modification response),and enforce the user plane rules received from the SMF. As an example,the UPF may enforce the at least one packet detection rule by matching auser data/traffic packet with service data flow template (e.g. servicedata flow filters and/or application identifiers), and may apply otheruser plane rules (e.g. forwarding action rule, QoS enforcement rule, andusage reporting rule) to the data/traffic packets matched the packetdetection rule. As an example, the UPF may enforce the at least oneforwarding action rule by forwarding, duplicating, dropping or bufferinga data/traffic packet respectively. As an example, the UPF may redirectthe traffic to a web portal of the operator. As an example, the UPF mayenforce the at least one usage reporting rule by measuring networkresources usage in terms of traffic data volume, duration (i.e. time)and/or events, according to a measurement method in the usage reportingrule; the UPF may report the network resources usage to the SMF when thequota/threshold reached, and/or event and/or another trigger is (are)met. As an example, the UPF may enforce the at least one QoS enforcementrule by applying at least one of QoS parameters: 5QI, ARP, MBR, GBR to aservice data flow; as an example, the UPF may enforce the at least oneQoS enforcement rule by applying at least one of QoS parameters: SessionAMBR and default 5QI/ARP combination to a PDU session.

As an example, the SMF and/or UPF may enforce the charging control rulesby performing at least one of the following actions: receiving, by theSMF, a charging control rule from a PCF; determining, by the SMF, atleast one of the user plane rules: at least one packet detection rule;at least one forwarding action rule; at least one QoS enforcement rule;or at least one usage reporting rule, sending, by the SMF to the UPF theat least one of the user plane rules; enforcing, by the UPF, the atleast one of the user plane rules; reporting, by the UPF, usage reportinformation to the SMF; sending, by the SMF, the usage reportinformation to the CHF. As an example, the usage report information maycomprise network resources usage in terms of traffic data volume,duration (i.e. time) applied to at least one of: a wireless device, aPDU session, a service data flow, an application, a network slice, or adata network.

In an example, other interactions may be performed by CHF, SMF, AMF,(R)AN and UE for the PDU session establishment procedure.

In an example, a CHF may update charging policy information to a PCF byinitiating charging policy information provision procedure during a PDUsession, the PCF may make policy decision based on the received chargingpolicy information and send to an SMF one or more updated PCC rulesand/or changing control rules. FIG. 18 shows an example call flow whichmay comprise one or more actions.

During a PDU session, a CHF may receive a trigger to update chargingpolicy information. As an example, the CHF may receive a trigger (e.g. amessage) from a billing domain (BD), e.g. the credit of a wirelessdevice has been updated. As an example, the CHF may receive a triggerfrom an OAM. As an example, the CHF may receive an internal trigger(e.g. a timer) based on local configuration and operator policies.

In response to the trigger received, the CHF may determine and updatecharging policy information based on the trigger. The charging policyinformation may comprise at least one of: an information elementindicating a first charging method/charging type, wherein the firstcharging method/charging type may comprise at least one of: onlinecharging, offline charging, or converged charging; an informationelement indicating at least one first charging rate; or an informationelement indicating at least one first identifier or address of a CHF.The first charging method/charging type and/or first charging rate maybe applied to at least one of: a PDU session identified by a PDU sessionidentifier; a service data flow identified by at least one service dataflow filter; an application identified by an application identifier; awireless device identified by at least one user identity (e.g. SUPI,PEI, and/or GPSI); a data network identified by a DNN; a network sliceidentified by a S-NSSAI and/or a network slice instance identifier.

As an example, the CHF may update the first charging method/chargingtype and/or the at least one first charging rate and/or the at least onefirst identifier or address of a CHF. As an example, the CHF may changethe first charging method/charging type from converged charging toonline charging. As an example, the CHF may change the at least onefirst charging rate from one value to a new value. As an example, theCHF may change the address of the CHF. As an example, the applied scopeof the charging policy information may be updated. As an example, theexisting charging policy information may be applied to a service dataflow, however, the updated charging policy information may be applied toa PDU session.

The CHF may send a message (e.g. charging policy information provision)to the PCF comprising the updated charging policy information, where thePCF may have already established a charging control session with theCHF. The message sent to the PCF may comprise at least one of: the atleast one UE identity (e.g. SUPI, PEI, and/or GPSI), the at least one UEIP address (e.g. UE IPv4 address and/or UE IPv6 network prefix), theDefault 5QI and default ARP, the Type of PDU Session (e.g. IPv4, IPv6,IPv4v6, Ethernet, Unstructured); the Access Type (e.g. 3GPP access); theRAT Type (e.g. 3GPP-NR-FDD); the PLMN identifier; the applicationidentifier; the DNN, the S-NSSAI(s) and/or network slice instanceidentifier(s), or the PDU Session ID.

In response to the message received from the CHF, the PCF may send tothe CHF a response message (e.g. charging policy information provisionack). The PCF may make policy decision based on the received updatedcharging policy information and may determine/update one or more PCCrules comprising one or more charging control rules. As an example, thePCF may determine keeping the existing PCC rules and/or charging controlrules unchanged. As an example, the PCF may update at least one of thefollowing rules in a PCC rule: at least one charging control rule; atleast one policy control rule comprising at least one QoS control ruleand/or at least one gating control rule; at least one usage monitoringcontrol rule; at least one application detection and control rule; atleast one traffic steering control rule; or at least one service dataflow detection information (e.g. service data flow template).

As an example, the PCF may update at least one of the followinginformation elements in a charging control rule: an information elementindicating a second charging method/charging type, wherein the secondcharging method/charging type may comprise at least one of: onlinecharging, offline charging, or converged charging; an informationelement indicating at least one second charging rate; or an informationelement indicating at least one second identifier or address of a CHF.

The PCF may send to the SMF a message (e.g. Policy Update Notify)comprising one or more updated PCC rules comprising one or more updatedcharging control rules. In response to the message received from thePCF, the SMF may send to the PCF a response message (Policy UpdateNotify Response). The SMF may install the one or more PCC rules and/orchanging control rules and other information received. The SMF mayenforce charging control rules by comprising at least one of thefollowing actions: based on the charging control rules and otherinformation elements, the SMF may construct a message (e.g. chargingdata request [update]) and send the constructed message to the CHF tomodify the charging session. The message sent to the CHF may comprise atleast one of the following updated information elements: an informationelement indicating an updated charging method/charging type, wherein thecharging method/charging type may comprise at least one of: onlinecharging, offline charging, or converged charging; an informationelement indicating at least one updated charging rate; an informationelement indicating a PDU session identified by a PDU session identifier;an information element indicating at least one service data flowidentified by at least one service data flow filter; an informationelement indicating an application identified by an applicationidentifier; an information element indicating a wireless deviceidentified by at least one user identity (e.g. SUPI, PEI, and/or GPSI);an information element indicating a data network identified by a DNN; aninformation element indicating a network slice identified by a S-NSSAIand/or a network slice instance identifier.

As an example, the SMF may indicate to the CHF an online chargingmethod; as an example, the SMF may indicated to the CHF an offlinecharging method; as an example, the SMF may indicate to the CHF aconverged charging method. In response to the message received from theSMF, the CHF may verify the information received and determine whetherto accept the charging session establishment request. As an example, theCHF may accept the request, and may send to the SMF a response message(e.g. charging data response). The response message may comprise atleast one of the following: an information element indicating a successcause value to indicate the session updating is success; an informationelement indicating an accepted charging method/charging type, whereinthe accepted charging method/charging type may comprise at least one of:online charging, offline charging, or converged charging; as an example,the accepted charging method/charging type may be the same as theupdated charging method/charging type; an information element indicatingat least one charging rate (e.g. rating group); an information elementindicating at least one granted unit (e.g. granted volume and/or grantedtime for online charging or converged charging); an information elementindicating final unit action (e.g. redirect the traffic to a web portalwhen the final granted unit has been consumed by the wireless device);an information element indicating a PDU session identified by a PDUsession identifier; an information element indicating at least oneservice data flow identified by at least one service data flow filter;an information element indicating an application identified by anapplication identifier; an information element indicating a wirelessdevice identified by at least one user identity (e.g. SUPI, PEI, and/orGPSI); an information element indicating a data network identified by aDNN; an information element indicating a network slice identified by aS-NSSAI and/or a network slice instance identifier; or an informationelement indicating a usage report.

As an example, the usage report information element may be used by theSMF to report current resource usage (e.g. volume, and/or time usage forthe current PDU session) before the charging rate is changed. As anexample, the CHF may reject the request, and may send to the SMF aresponse message (e.g. charging data response) comprising a proposedcharging method/charging type. The response message may comprise atleast one of the following: an information element indicating a rejectcause value to indicate the request is rejected; an information elementindicating an accepted charging method/charging type, wherein theaccepted charging method/charging type proposed by the CHF may compriseat least one of: online charging, offline charging, or convergedcharging; as an example, the accepted charging method/charging type maybe different from the requested charging method/charging type. As anexample, the requested charging method may be offline charging, and theproposed accepted charging method may be converged charging.

In response to the message received from the CHF, the SMF may takedifferent actions based on the result of the response.

As an example, when receiving a reject response message from the CHF,the SMF may resend to the CHF a second request message (e.g. chargingdata request) comprising the accepted charging method/charging typeproposed by the CHF. As an example, the requested charging method in thesecond request message may be set as the proposed accepted chargingmethod in the response message (e.g. converged charging). The CHF mayaccept the second request by sending to the CHF a second responsemessage (e.g. charging data response) comprising a success cause valueindicating the request is accepted.

As an example, when receiving a reject response message from the CHF,the SMF may select a second CHF from the information (e.g. chargingpolicy rules) received from the PCF and send a request message (e.g.charging data request) to the second CHF to establish a chargingsession. As an example, after receiving a success response message fromthe CHF, the SMF may enforce the updated PCC rules and/or updatedcharging control rules required by the PCF and/or charging functionrequired by the CHF by determining/updating at least one of thefollowing user plane rules based on the received updated PCC rulesand/or updated charging control rules from the PCF and/or theinformation (e.g. charging policy information) received from the CHF: atleast one packet detection rule; at least one forwarding action rule; atleast one QoS enforcement rule; or at least one usage reporting rule.

As an example, the SMF may enforce the updated PCC rules and/or updatedcharging control rules required by the PCF and/or charging functionrequired by the CHF by sending to the UPF a message (e.g. N4 sessionmodification request) comprising the at least one of the followingupdated user plane rules: at least one packet detection rule; at leastone forwarding action rule; at least one QoS enforcement rule; or atleast one usage reporting rule. As an example, the SMF may not send amessage to the UPF to update the rules and keep the existing rules inthe UPF unchanged. In response to the message received from the SMF, theUPF may install the user plane rules, send to the SMF a response message(e.g. N4 session modification response). As an example, the UPF mayenforce the updated user plane rules received from the SMF.

In an example, a policy control function may receive from a sessionmanagement function, a first message requesting a charging control rulefor a packet data unit session of a wireless device. In an example, thepolicy control function may send to a charging function and in responseto the first message, a second message requesting a charging policyinformation for the packet data unit session. In an example, the policycontrol function may receive from the charging function a third messagecomprising at least one charging policy information. In an example, thepolicy control function may determine at least one charging control rulefor the packet data unit session based on the at least one chargingpolicy information. In an example, the policy control function may sendto the session management function, a fourth message comprising the atleast one charging control rule. In an example, the session managementfunction may enforce the at least one charging control rule. In anexample, the at least one charging policy information may comprises atleast one of: an information element indicating a charging methodapplicable for the at least one packet data unit session; an informationelement indicating a charging rate applicable for the at least onepacket data unit session; or an information element indicating anaddress of the charging function. In an example, the charging method maycomprise at least one of: an information element indicating that anonline charging is applicable for the packet data unit session; aninformation element indicating that an offline charging is applicablefor the packet data unit session; or an information element indicatingthat a converged charging is applicable for the packet data unitsession. In an example, the session management function may send to auser plane function, a fifth message requesting to establish or modify aN4 session, the fifth message may comprise the at least one chargingcontrol rule for the packet data unit session and the wireless device;In an example, the session management function may receive from the userplane function, a sixth message in response to the fifth message.

In an example, the session management function may send to the chargingfunction, a seventh message requesting to establish a charging session,the seventh message may comprise a charging method indication. In anexample, the session management function may receive from the chargingfunction, an eighth message in response to the seventh message. In anexample, the charging method indication may comprise at least one of: aninformation element indicating an online charging; an informationelement indicating an offline charging; or an information elementindicating a converged charging. In an example, the first message maycomprise at least one of: an identifier of the wireless device; or anidentifier of the packet data unit session. In an example, the at leastone charging control rule may comprise at least one of: a chargingpolicy; a quality of service policy; or a gating policy. In an example,a charging function may receive from a policy control function, a firstmessage requesting at least one charging policy for a packet data unitsession and a wireless device. In an example, the charging function maydetermine the at least one charging policy for the packet data unitsession and the wireless device.

In an example, the charging function may send to the policy controlfunction, a second message in response to the first message, the secondmessage may comprise the at least one charging policy for the packetdata unit session and the wireless device; wherein the charging policymay comprise an information element indicating a charging rate. In anexample, the charging function may receive from a session managementfunction, a third message requesting to establish a charging session,wherein the third message comprising at least one of: an informationelement indicating a charging rate; or an information element indicatinga charging type. In an example, the charging function may send to thesession management function, a fourth message in response to the thirdmessage. In an example, the charging type indication may comprise atleast one of: an information element indicating an online charging; aninformation element indicating an offline charging; or an informationelement indicating a converged charging.

According to various embodiments, one or more devices such as, forexample, a wireless device, off-network wireless device, a base station,a core network device, and/or the like, may be employed in a system. Oneor more of the devices may be configured to perform particularoperations or actions by virtue of having software, firmware, hardware,or a combination of them installed on the one or more of the devices,that in operation causes or cause the one or more devices to perform theactions. One or more computer programs can be configured to performparticular operations or actions by virtue of including instructionsthat, when executed by data processing apparatus, cause the apparatus toperform the actions. Embodiments of example actions are illustrated inthe accompanying figures and specification. Features from variousembodiments may be combined to create yet further embodiments.

FIG. 20 is a flow diagram of an aspect of an embodiment of the presentdisclosure. At 2010, a policy control function (PCF) may receive from asession management function (SMF), a policy establishment requestmessage requesting a charging control rule for a packet data unit (PDU)session of a wireless device. At 2020, in response to the policyestablishment request message, the PCF may send to a charging function(CHF), a charging policy request message requesting charging policyinformation for the PDU session. At 2030, the PCF may receive from theCHF, a charging policy response message comprising the charging policyinformation. The charging policy information comprises a first chargingmethod. At 2040, the PCF may determine a charging control rule for thePDU session based on the charging policy information. At 2050, the PCFmay send to the SMF, a policy establishment response message. The policyestablishment response message may comprise the charging control rule.At 2060, the SMF may enforce the charging control rule.

According to an example embodiment, the charging policy request messagemay comprise an identifier of the wireless device. According to anexample embodiment, the charging policy request message may comprise aUE IP address. According to an example embodiment, the charging policyrequest message may comprise an identifier of the PDU session. Accordingto an example embodiment, the PCF may send to the CHF, the chargingpolicy request message via a network function. According to an exampleembodiment, the CHF may determine the charging policy information forthe PDU session based on an identifier of the wireless device. Accordingto an example embodiment, the CHF may determine the charging policyinformation for the PDU session based on a type of PDU session.According to an example embodiment, the CHF may determine the chargingpolicy information for the PDU session based on an access type.According to an example embodiment, the CHF may determine the chargingpolicy information for the PDU session based on a radio accesstechnology (RAT) type. According to an example embodiment, the CHF maydetermine the charging policy information for the PDU session based on apublic land mobile network (PLMN) identifier. According to an exampleembodiment, the CHF may determine the charging policy information forthe PDU session based on an application identifier. According to anexample embodiment, the CHF may determine the charging policyinformation for the PDU session based on a data network name (DNN).According to an example embodiment, the CHF may determine the chargingpolicy information for the PDU session based on a single network sliceselection assistance information (S-NSSAI). According to an exampleembodiment, the CHF may determine the charging policy information forthe PDU session based on a session identifier of the PDU session.According to an example embodiment, the CHF may determine the chargingpolicy information for the PDU session based on user locationinformation.

According to an example embodiment, the charging policy information maycomprise an information element indicating a first charging rate isapplicable for the PDU session. According to an example embodiment, thecharging policy information may comprise an address of a first chargingfunction. According to an example embodiment, based on the chargingpolicy information, the SMF may determine a policy and charging control(PCC) rule for the PDU session. According to an example embodiment, thePCC rule may comprise a charging control rule. According to an exampleembodiment, the PCC rule may comprise a policy control rule. Accordingto an example embodiment, the policy control rule may comprise a QoScontrol rule. According to an example embodiment, the policy controlrule may comprise a gating control rule. According to an exampleembodiment, the PCC rule may comprise a usage monitoring control rule.According to an example embodiment, the PCC rule may comprise anapplication detection and control rule. According to an exampleembodiment, the PCC rule may comprise a traffic steering control rule.According to an example embodiment, the PCC rule may comprise a servicedata flow detection information.

According to an example embodiment, the charging control rule maycomprise an information element indicating a second charging method.According to an example embodiment, the charging control rule maycomprise an information element indicating a second charging rate.According to an example embodiment, the charging control rule maycomprise an information element indicating an identifier or address of asecond CHF. According to an example embodiment, the second chargingmethod may comprise an information element indicating that an onlinecharging is applicable for the PDU session. According to an exampleembodiment, the second charging method may comprise an informationelement indicating that an offline charging is applicable for the PDUsession. According to an example embodiment, the second charging methodmay comprise an information element indicating that a converged chargingis applicable for the PDU session.

According to an example embodiment, the enforcing the charging controlrule by the SMF may comprise sending, by the SMF to the CHF, a chargingdata request message requesting to establish a charging session, and thecharging data request message may comprise a requested charging methodindication. According to an example embodiment, the enforcing thecharging control rule by the SMF may comprise receiving, by the SMF fromthe CHF, a charging data response message comprising an acceptedcharging method indication. According to an example embodiment, therequested charging method indication may comprise an information elementindicating an online charging. According to an example embodiment, therequested charging method indication may comprise an information elementindicating an offline charging. According to an example embodiment, therequested charging method indication may comprise an information elementindicating a converged charging. According to an example embodiment, theaccepted charging method indication may comprise an information elementindicating an online charging. According to an example embodiment, theaccepted charging method indication may comprise an information elementindicating an offline charging. According to an example embodiment, theaccepted charging method indication may comprise an information elementindicating a converged charging.

According to an example embodiment, the SMF may determine a user planerule for the PDU session based on the charging control rule. Accordingto an example embodiment, the SMF may determine a user plane rule forthe PDU session based on charging policy information received from theCHF. According to an example embodiment, the SMF may send to a userplane function (UPF), a N4 request message requesting to establish ormodify a session. The N4 request message may comprise the user planerule for the PDU session and the wireless device. According to anexample embodiment, the UPF may enforce the user plane rule. Accordingto an example embodiment, the N4 request message may comprise an N4session identifier for the PDU session. According to an exampleembodiment, the session is an N4 session. According to an exampleembodiment, the user plane rule may comprise a packet detection rule.According to an example embodiment, the user plane rule may compriseforwarding action rule. According to an example embodiment, the userplane rule may comprise a QoS enforcement rule. According to an exampleembodiment, the user plane rule may comprise a usage reporting rule.According to an example embodiment, the enforcing the user plane rule bythe UPF may comprise sending, by the UPF to the SMF, a resource usagereport for the PDU session. According to an example embodiment, theenforcing the user plane rule by the UPF may comprise receiving, by theUPF from the SMF, a response message to the resource usage report.

According to an example embodiment, an NRF may receive from the PCF, aCHF selection request message comprising PDU session information.According to an example embodiment, the NRF may determine an address ofa CHF based on the PDU session information. According to an exampleembodiment, the NRF may send to the PCF, the address of the CHF.

According to an example embodiment, the PDU session information maycomprise a UE IP address. According to an example embodiment, the PDUsession information may comprise a type of PDU Session. According to anexample embodiment, the PDU session information may comprise an accesstype. According to an example embodiment, the PDU session informationmay comprise a radio access technology (RAT) type. According to anexample embodiment, the PDU session information may comprise userlocation information. According to an example embodiment, the PDUsession information may comprise information of the SMF for the PDUsession.

FIG. 21 is a flow diagram of an aspect of an embodiment of the presentdisclosure. At 2110, a charging function (CHF) may receive from a policycontrol function (PCF), a first message requesting charging policyinformation for a packet data unit (PDU) session and a wireless device.At 2120, the CHF may determine the charging policy information for thePDU session and the wireless device. At 2130, the CHF may send to thePCF, a second message in response to the first message, the secondmessage may comprise the charging policy information. According to anexample embodiment, the charging policy information may comprise aninformation element indicating a first charging method. According to anexample embodiment, the charging policy information may comprise aninformation element indicating a first charging rate. According to anexample embodiment, the charging policy information may comprise aninformation element indicating an identifier or address of a CHF. At2140, the CHF may receive from the SMF, a third message requesting toestablish a charging session. The third message may comprise a requestedcharging method indication. At 2150, the CHF may send to the SMF, afourth message comprising an accepted charging method indication.

According to an example embodiment, the requested charging methodindication may comprise an information element indicating an onlinecharging. According to an example embodiment, the requested chargingmethod indication may comprise an information element indicating anoffline charging. According to an example embodiment, the requestedcharging method indication may comprise an information elementindicating a converged charging. According to an example embodiment, theaccepted charging method indication may comprise an information elementindicating an online charging. According to an example embodiment, theaccepted charging method indication may comprise an information elementindicating an offline charging. According to an example embodiment, theaccepted charging method indication may comprise an information elementindicating a converged charging.

In this specification, “a” and “an” and similar phrases are to beinterpreted as “at least one” and “one or more.” In this specification,the term “may” is to be interpreted as “may, for example.” In otherwords, the term “may” is indicative that the phrase following the term“may” is an example of one of a multitude of suitable possibilities thatmay, or may not, be employed to one or more of the various Examples. IfA and B are sets and every element of A is an element of B, A is calleda subset of B. In this specification, only non-empty sets and subsetsare considered. For example, possible subsets of B={cell1, cell2} are:{call1}, {cell2}, and {can, cell2}.

In this specification, various Examples are disclosed. Limitations,features, and/or elements from the disclosed example Examples may becombined to create further Examples within the scope of the disclosure.

In this specification, various Examples are disclosed. Limitations,features, and/or elements from the disclosed example Examples may becombined to create further Examples within the scope of the disclosure.

In this specification, parameters (Information elements: IEs) maycomprise one or more objects, and one of those objects may comprise oneor more other objects. For example, if parameter (IE) N comprisesparameter (IE) M, and parameter (IE) M comprises parameter (IE) K, andparameter (IE) K comprises parameter (information element) J, then, forexample, N comprises K, and N comprises J. In an example, when one ormore messages comprise a plurality of parameters, it implies that aparameter in the plurality of parameters is in at least one of the oneor more messages, but does not have to be in one of the one or moremessages.

Many of the elements described in the disclosed Examples may beimplemented as modules. A module is defined here as an isolatableelement that performs a defined function and has a defined interface toother elements. The modules described in this disclosure may beimplemented in hardware, software in combination with hardware,firmware, wetware (e.g. hardware with a biological element) or acombination thereof, some of which are behaviorally equivalent. Forexample, modules may be implemented as a software routine written in acomputer language configured to be executed by a hardware machine (suchas C, C++, Fortran, Java, Basic, Matlab or the like) or amodeling/simulation program such as Simulink, Stateflow, GNU Octave, orLabVIEWMathScript. Additionally, it may be possible to implement modulesusing physical hardware that incorporates discrete or programmableanalog, digital and/or quantum hardware. Examples of programmablehardware comprise: computers, microcontrollers, microprocessors,application-specific integrated circuits (ASICs); field programmablegate arrays (FPGAs); and complex programmable logic devices (CPLDs).Computers, microcontrollers and microprocessors are programmed usinglanguages such as assembly, C, C++ or the like. FPGAs, ASICs and CPLDsare often programmed using hardware description languages (HDL) such asVHSIC hardware description language (VHDL) or Verilog that configureconnections between internal hardware modules with lesser functionalityon a programmable device. Finally, it needs to be emphasized that theabove mentioned technologies are often used in combination to achievethe result of a functional module.

The disclosure of this patent document incorporates material which issubject to copyright protection. The copyright owner has no objection tothe facsimile reproduction by anyone of the patent document or thepatent disclosure, as it appears in the Patent and Trademark Officepatent file or records, for the limited purposes required by law, butotherwise reserves all copyright rights whatsoever.

While various Examples have been described above, it should beunderstood that they have been presented by way of example, and notlimitation. It will be apparent to persons skilled in the relevantart(s) that various changes in form and detail can be made thereinwithout departing from the spirit and scope. In fact, after reading theabove description, it will be apparent to one skilled in the relevantart(s) how to implement alternative Examples. Thus, the present Examplesshould not be limited by any of the above described exemplary Examples.In particular, it should be noted that, for example purposes, the aboveexplanation has focused on the example(s) using 5G AN. However, oneskilled in the art will recognize that Examples of the invention may beimplemented in a system comprising one or more legacy systems or LTE.The disclosed methods and systems may be implemented in wireless orwireline systems. The features of various Examples presented in thisinvention may be combined. One or many features (method or system) ofone Example may be implemented in other Examples. A limited number ofexample combinations are shown to indicate to one skilled in the art thepossibility of features that may be combined in various Examples tocreate enhanced transmission and reception systems and methods.

In addition, it should be understood that any figures which highlightthe functionality and advantages, are presented for example purposes.The disclosed architecture is sufficiently flexible and configurable,such that it may be utilized in ways other than that shown. For example,the actions listed in any flowchart may be re-ordered or optionally usedin some examples.

Further, the purpose of the Abstract of the Disclosure is to enable theU.S. Patent and Trademark Office and the public generally, andespecially the scientists, engineers and practitioners in the art whoare not familiar with patent or legal terms or phraseology, to determinequickly from a cursory inspection the nature and essence of thetechnical disclosure of the application. The Abstract of the Disclosureis not intended to be limiting as to the scope in any way.

Finally, it is the applicant's intent that only claims that include theexpress language “means for” or “step for” be interpreted under 35U.S.C. 112. Claims that do not expressly include the phrase “means for”or “step for” are not to be interpreted under 35 U.S.C. 112.

What is claimed is:
 1. A method comprising: receiving, by a charging function (CHF) from a policy control function (PCF), a first request for charging policy information for a packet data unit (PDU) session of a wireless device; determining, by the CHF, the charging policy information for the PDU session of the wireless device, wherein the charging policy information indicates a charging method comprising one or more of: online charging; offline charging; and converged charging; sending, by the CHF to the PCF, a message comprising the charging policy information; receiving, by the CHF from a session management function (SMF), a second request to establish a charging session, wherein the second request comprises the charging method; and sending, by the CHF to the SMF, a confirmation for the charging method.
 2. The method of claim 1, wherein the first request comprises at least one of: an identifier of the wireless device; a UE IP address; or an identifier of the PDU session.
 3. The method of claim 1, further comprising receiving, by the CHF from the PCF, the first request via a network function.
 4. The method of claim 1, wherein the determining is based on at least one of: an identifier of the wireless device; a type of PDU session; an access type; a radio access technology (RAT) type; a public land mobile network (PLMN) identifier; an application identifier; a data network name (DNN); a single network slice selection assistance information (S-NSSAI); the identifier of the PDU session; or user location information.
 5. The method of claim 1, wherein the charging policy information further comprises a charging rate applied to the PDU session.
 6. The method of claim 5, wherein the second request comprises the charging rate.
 7. The method of claim 1, wherein the charging policy information further comprises an address of the CHF applied to the PDU session.
 8. The method of claim 7, wherein the second request comprises the address of the CHF.
 9. The method of claim 1, wherein the second request further comprises a requested charging method indication, wherein the requested charging method indication comprises at least one of: an information element indicating a requested online charging; an information element indicating a requested offline charging; or an information element indicating a requested converged charging.
 10. The method of claim 1, further comprising sending, by CHF to the SMF, a charging data response message comprising an accepted charging method indication, wherein the accepted charging method indication comprises at least one of: an information element indicating an accepted online charging; an information element indicating an accepted offline charging; or an information element indicating an accepted converged charging.
 11. An apparatus comprising: one or more processors; and memory storing instructions that, when executed by the one or more processors, cause a charging function (CHF) to: receive, from a policy control function (PCF), a first request for charging policy information for a packet data unit (PDU) session of a wireless device; determine the charging policy information for the PDU session of the wireless device, wherein the charging policy information indicates a charging method comprising one or more of: online charging; offline charging; and converged charging; send, to the PCF, a message comprising the charging policy information; receive, by the CHF from a session management function (SMF), a second request to establish a charging session, wherein the second request comprises the charging method; and send, to the SMF, a confirmation for the charging method.
 12. The apparatus of claim 11, wherein the first request comprises at least one of: an identifier of the wireless device; a UE IP address; or an identifier of the PDU session.
 13. The apparatus of claim 11, wherein the instructions, when executed by the one or more processors, further cause the apparatus to receive, from the PCF, the first request via a network function.
 14. The apparatus of claim 11, wherein the determination is based on at least one of: an identifier of the wireless device; a type of PDU session; an access type; a radio access technology (RAT) type; a public land mobile network (PLMN) identifier; an application identifier; a data network name (DNN); a single network slice selection assistance information (S-NSSAI); the identifier of the PDU session; or user location information.
 15. The apparatus of claim 11, wherein the charging policy information further comprises a charging rate applied to the PDU session.
 16. The apparatus of claim 15, wherein the second request comprises the charging rate.
 17. The apparatus of claim 11, wherein the charging policy information further comprises an address of the CHF applied to the PDU session.
 18. The apparatus of claim 11, wherein the second request further comprises a requested charging method indication, wherein the requested charging method indication comprises at least one of: an information element indicating a requested online charging; an information element indicating a requested offline charging; or an information element indicating a requested converged charging.
 19. The apparatus of claim 11, wherein the instructions, when executed by the one or more processors, further cause the apparatus to send, to the SMF, a charging data response message comprising an accepted charging method indication, wherein the accepted charging method indication comprises at least one of: an information element indicating an accepted online charging; an information element indicating an accepted offline charging; or an information element indicating an accepted converged charging.
 20. A system comprising: a policy control function (PCF); a session management function (SMF); and an apparatus comprising: one or more processors; and memory storing instructions that, when executed by the one or more processors, cause a charging function (CHF) to: receive, from the PCF, a first request for charging policy information for a packet data unit (PDU) session of a wireless device; determine the charging policy information for the PDU session of the wireless device, wherein the charging policy information indicates a charging method comprising one or more of: online charging; offline charging; and converged charging; send, to the PCF, a message comprising the charging policy information; receive, by the CHF from the SMF, a second request to establish a charging session, wherein the second request comprises the charging method; and send, to the SMF, a confirmation for the charging method. 